The age of empire

WEBVTT
Kind: captions
Language: en

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- [Voiceover] So I have a map here

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of United States
possessions in the Pacific

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and in the Caribbean today,

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and they're kind of all over the place.

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And some of them are pretty tiny.

00:00:14.563 --> 00:00:15.746
There's Guam,

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which is just barely a
little speck on the map,

00:00:18.441 --> 00:00:20.855
and American Samoa

00:00:20.855 --> 00:00:24.825
and more well known would be
the Hawaiian Islands, right?

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One of the fifty states
of the United States.

00:00:28.238 --> 00:00:32.024
Have you ever wondered
why the United States

00:00:32.024 --> 00:00:35.298
has islands in the middle of the Pacific?

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This is thousands of
miles from the mainland

00:00:39.896 --> 00:00:41.981
of the United States.

00:00:41.981 --> 00:00:43.908
So what's the deal?

00:00:43.908 --> 00:00:46.067
Did the United States just want access

00:00:46.067 --> 00:00:47.693
to somewhere to get a tan

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and maybe buy some pineapple?

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In this video I want to
talk about the very unique,

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historical circumstances under which

00:00:56.864 --> 00:00:59.906
the United States acquired
a bunch of territory

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outside of the borders
of the lower 48 states.

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Or how, in other words,

00:01:06.019 --> 00:01:09.596
the United States became an empire.

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And empire,

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or imperialism,

00:01:15.407 --> 00:01:20.191
is the practice of having
political or economic

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control over a territory that is outside

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the boundaries of your nation.

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So when did this happen
and why did this happen?

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Let me give you a little background

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on the run up to the United
States becoming an empire.

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So the Civil War ends in 1865,

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and while that is a conflict

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just within the United States,

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right, the definition of civil war,

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the Civil War has kind
of an interesting effect

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on the United States' economy

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because for the the
course of the Civil War

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the North

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really ramped up their
industrial production

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to win the war.

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So they build railroad tracks
and they have factories

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that help them build the armaments

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that are gonna help them
with victory in the war.

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Well, after the war,

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all these factories, all
these railroads still exist,

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and they're turned to different purposes.

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So over the course of
the late 19th century

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from the end of the Civil War,

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really up until even 1900 and beyond,

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the United States becomes the leading

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industrial power in the world.

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So they make more stuff

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than anybody else,

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and this is one of the reasons why so many

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immigrants are flocking
to the United States

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in this time period,

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because there are jobs in factories.

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But even though the U.S. was acknowledged

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as this great industrial power,

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it was not really acknowledged as

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a world military power.

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The number one power in the world

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at this time is England.

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This is the end of the Victorian Era.

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None of the nations of Europe
think of the United States

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as an important power in the world.

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If you were a diplomat from France

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and you got a diplomatic
posting to Washington D.C.,

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that would be like getting a
diplomatic posting on the moon.

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There is nothing going on there.

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Nobody's interested.

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You'd much rather be in Vienna or London.

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But another reason why
the nations of Europe

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are such important world powers is because

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of their own investment in imperialism.

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So let me show you a map
of the world in 1914,

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which is kind of after
this age of imperialism,

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but it gives you an idea
of how much territory

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Europe had gobbled up in this time period.

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So this is the rest of the
world in this time period,

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and we're talking about kind of the period

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from about 1880 to 1900,

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and in this time period
the powers of Europe

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really competed with
each other to take over

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territories in the rest of the world.

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And these would have
been developing nations,

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nations that did not have the firepower

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to compete with Europe,

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and they were generally nations with

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a lot of natural resources.

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So in the mid-19th century,

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there'd been explorers
going throughout Africa.

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This is the period of Dr.
Livingstone, I presume,

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and Dr. Livingstone
reports back to England

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that there is a lot of stuff in Africa.

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We're talkin' about diamonds

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and gold

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and rubber,

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and elsewhere in the world,

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in India there's tea.

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And so in the 1880s, 1890s,

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Europe scrambles for
territorial control of Africa

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and you see England here in South Africa,

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and France up here in northwest Africa,

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and then of course you've got England

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in India and Australia

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and they're even fighting
for influence in China.

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And they had two main reasons for wanting

00:05:04.044 --> 00:05:05.554
these colonies abroad.

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One is, as we said,
their natural resources,

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so they can take all the raw materials,

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the unfinished goods,

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to run the empire and
then they can take that

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back up to Europe and process it.

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So it's a cheap source of stuff

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for their industrial production.

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The other thing they want is markets,

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so all of these territories,
all of these colonies,

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have people in them who
can buy the products

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from the European nations,

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and as their factories
produce more and more stuff,

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they needed more and more
people to buy those things

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or they're going to stagnate economically.

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So this is where the
United States comes in.

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So in the late 19th century the U.S.

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has become this leading industrial power.

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They feel like they're
not getting any respect

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from Europe for being pretty big dogs,

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but they also start looking
at this scramble for Africa,

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this scramble for colonies in the world,

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and they think maybe the United States

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should get in on this game,

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and they have a couple of
reasons for doing this.

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One of the reasons for
doing this is the idea

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of expanding the frontier.

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So in the late 19th century,

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there was a pretty famous historian

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by the name of Frederick Jackson Turner.

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And what Turner has to say really troubles

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a lot of people.

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He says manifest destiny is done.

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So manifest destiny you'll recall,

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is this idea that God
wanted the United States

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to occupy the North American continent

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from Atlantic to Pacific.

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As of 1890, the census showed
that there was pretty much

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even population distribution all the way

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to the Pacific Ocean,

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so this process of conquering the frontier

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that many white Americans thought was

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really crucial to the
American spirit, was over.

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So what is the United States going to do?

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Culturally they pride themselves on being

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a pioneering people.

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But along with that goes the same

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sort of quest for new markets that Europe

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is going through in the same time period.

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So if the United States is the world's

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leading industrial power,

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and they did that by
conquering the frontier,

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building railroads,

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finding new people to sell the
products of their factory to,

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what's going to happen if they have

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nowhere else to expand?

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Relentless expansion
is kind of the backbone

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of American capitalism.

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And so people started to worry that

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if expansion is done,

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then the American industrial project

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is going to falter with
no new markets to conquer.

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All right, so those are
the economic and cultural

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explanations for why the United States

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became interested in
being an imperial power

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at the end of the 19th century.

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There are also some military explanations,

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so let me take you back
to a map of the Pacific.

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So in 1890, this man
named Alfred Thayer Mahan

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published a book called The Influence

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of Sea Power Upon History.

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And Mahan's thesis

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was that all the great

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nations of history since time immemorial

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had gotten their greatness through

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a domination of the seas.

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So he says that if the United States

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really wants to be a
world power going forward,

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they're going to have to make some serious

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investments in their navy.

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He says first they're
going to have to build

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a really powerful naval fleet,

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which has never really
been the bread and butter

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of America's military.

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Up until this point,

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the United States' navy
was like five leaky boats.

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So he says they have to
build a powerful navy

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and that you should
consider putting a canal

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somewhere across Central America

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so that if a ship is in the Atlantic

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it doesn't have to go all
the way around South America

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to get to the Pacific.

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It can just cut this corner here.

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And the last thing that Mahan says is that

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the U.S. is going to need friendly ports

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all over the world so that this navy

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can dock places, refuel,
take on new supplies,

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because if your ports
are only on the edges

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of the United States,

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it could take you days and days and days

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to make it all the way over to Asia.

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So Mahan says we need good
harbors along the way.

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And you know what's a really great harbor?

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Pearl Harbor in Hawaii.

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It's one of the best harbors in the world.

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And basically in the
future the U.S. government

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is going to to do exactly what Mahan says.

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In between 1890 and 1914,

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the United States
increases their investment

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in the navy by a power of seven.

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It's $22 million dollars only in 1890.

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By 1914 they're putting
$140 million dollars

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a year into their navy.

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And they will move forward with this plan

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to build a canal somewhere
in Central America.

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Hint, hint, it might be in Panama.

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And they will annex ports
all over the Pacific,

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and also in the Caribbean,

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to take care of their new powerful navy.

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So in the late 19th century,

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the U.S. is really poised
to enter into world politics

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as a major world power.

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In the next video I'll talk
about the Spanish American War

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of 1898 and how that led the United States

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to become an empire.


2015 AP Chemistry free response 1 b c

WEBVTT
Kind: captions
Language: en

00:00:00.282 --> 00:00:01.805
- [Voiceover] All right, part b.

00:00:01.805 --> 00:00:06.453
A fresh zinc air cell is
weighed on an analytical balance

00:00:06.453 --> 00:00:10.029
before being placed in
a hearing aid for use.

00:00:10.029 --> 00:00:13.085
As the cell operates,
does the mass of the cell

00:00:13.085 --> 00:00:15.973
increase, decrease, or remain the same?

00:00:15.973 --> 00:00:19.973
Justify your answer to
part b one, or b i, b one

00:00:20.918 --> 00:00:24.297
in terms of the equation for
the overall cell reaction.

00:00:24.297 --> 00:00:26.178
So let's just think about
it for a little bit.

00:00:26.178 --> 00:00:28.790
Does the mass of the
cell increase, decrease,

00:00:28.790 --> 00:00:30.427
or remain the same?

00:00:30.427 --> 00:00:32.273
Well, let's go to our
original reaction over here.

00:00:32.273 --> 00:00:33.806
This is our total reaction.

00:00:33.806 --> 00:00:37.637
The zinc is part of the metal air cell,

00:00:37.637 --> 00:00:38.970
so that would contribute

00:00:38.970 --> 00:00:41.053
to its weight beforehand,

00:00:43.035 --> 00:00:45.431
and then it reacts with the oxygen.

00:00:45.431 --> 00:00:47.486
Well, where is this oxygen coming from?

00:00:47.486 --> 00:00:49.959
Well, this is oxygen
is coming from the air

00:00:49.959 --> 00:00:52.989
and essentially gets
incorporated into the zinc.

00:00:52.989 --> 00:00:56.089
So, before, the oxygen is in the air,

00:00:56.089 --> 00:00:58.701
but then after the reaction,
after the total reaction,

00:00:58.701 --> 00:01:01.406
it gets incorporated with the
zinc, I guess I should say,

00:01:01.406 --> 00:01:02.264
not into the zinc, of course.

00:01:02.264 --> 00:01:06.022
It gets incorporated with
the zinc as zinc oxide,

00:01:06.022 --> 00:01:09.389
and so now, the oxygen
is part of the cell.

00:01:09.389 --> 00:01:13.261
Part, or contributes
to weight of the cell.

00:01:13.261 --> 00:01:14.678
So, contributes,

00:01:15.820 --> 00:01:17.070
contributes to

00:01:19.153 --> 00:01:20.070
the weight,

00:01:21.662 --> 00:01:22.749
the weight of cell.

00:01:22.749 --> 00:01:24.306
It doesn't contribute before the reaction,

00:01:24.306 --> 00:01:26.562
but it contributes after the reaction.

00:01:26.562 --> 00:01:29.626
So our, the mass, and
I guess you could say,

00:01:29.626 --> 00:01:32.597
the weight, is going to increase.

00:01:32.597 --> 00:01:34.931
So I'll just write increase.

00:01:35.964 --> 00:01:39.903
And part two, we need
to justify our answer

00:01:39.903 --> 00:01:42.395
in terms of the equation for
the overall cell reaction.

00:01:42.395 --> 00:01:44.684
So let me just write the
overall cell reaction.

00:01:44.684 --> 00:01:46.601
So, two zinc molecules

00:01:47.690 --> 00:01:50.502
react with one molecular oxygen,

00:01:50.502 --> 00:01:52.169
one O_two, to yield

00:01:53.398 --> 00:01:54.648
two zinc oxide,

00:01:57.280 --> 00:01:59.368
two zinc oxide molecules.

00:01:59.368 --> 00:02:00.647
Well, what we could say is,

00:02:00.647 --> 00:02:05.471
is that this was not part
of cell before reaction,

00:02:05.471 --> 00:02:06.387
not part of

00:02:09.640 --> 00:02:11.630
cell before reaction.

00:02:11.630 --> 00:02:13.279
It's coming from the air.

00:02:13.279 --> 00:02:14.612
Before reaction.

00:02:16.242 --> 00:02:20.114
And then we could say, part
of cell after reaction.

00:02:20.114 --> 00:02:21.197
Part of cell

00:02:23.590 --> 00:02:24.840
after reaction.

00:02:26.496 --> 00:02:29.357
And we could write it
out in words, if we like.

00:02:29.357 --> 00:02:30.607
After reaction.

00:02:31.545 --> 00:02:33.878
And so I could say, oxygen,

00:02:35.148 --> 00:02:36.981
oxygen comes from air,

00:02:40.669 --> 00:02:41.919
from, from air,

00:02:46.056 --> 00:02:49.827
air to be incorporated
into the zinc oxide,

00:02:49.827 --> 00:02:51.327
to be incorporated

00:02:55.787 --> 00:02:57.037
into zinc oxide

00:02:59.861 --> 00:03:03.277
which then contributes to weight of cell,

00:03:04.137 --> 00:03:05.593
or to the mass of cell.

00:03:05.593 --> 00:03:07.427
Which then contributes

00:03:10.107 --> 00:03:12.194
to mass of cell,

00:03:12.194 --> 00:03:13.027
to mass

00:03:15.814 --> 00:03:16.648
of cell.

00:03:18.474 --> 00:03:20.134
All right, I think I feel
pretty good about that.

00:03:20.134 --> 00:03:22.153
Now let's do part c.

00:03:22.153 --> 00:03:25.284
The zinc-air cell is taken
to the top of a mountain

00:03:25.284 --> 00:03:27.776
where the air pressure is lower.

00:03:27.776 --> 00:03:31.143
Will the cell potential be
higher, lower, or the same

00:03:31.143 --> 00:03:33.432
as the cell potential
at the lower elevation?

00:03:33.432 --> 00:03:36.260
Justify your answer to the first part

00:03:36.260 --> 00:03:38.786
based on the equation for
the overall cell reaction

00:03:38.786 --> 00:03:40.570
and the information above.

00:03:40.570 --> 00:03:44.476
Well, let me just write the
overall cell reaction again.

00:03:44.476 --> 00:03:47.981
So let me, the overall cell reaction.

00:03:47.981 --> 00:03:49.126
I'll rewrite it again.

00:03:49.126 --> 00:03:51.626
So we have two zinc molecules.

00:03:54.132 --> 00:03:56.156
Let me write that a little bit neater.

00:03:56.156 --> 00:03:58.824
Two, and I wrote it messier.

00:03:58.824 --> 00:04:00.408
Two zinc molecules.

00:04:01.855 --> 00:04:03.033
One molecular oxygen.

00:04:03.033 --> 00:04:04.447
We're going to have this
ingrained in our brain

00:04:04.447 --> 00:04:05.281
by the time this is done,

00:04:05.281 --> 00:04:07.235
I'm writing it so frequently.

00:04:07.235 --> 00:04:08.985
We get two zinc oxides.

00:04:08.985 --> 00:04:10.319
Two zinc oxides.

00:04:12.655 --> 00:04:14.002
And so what's going to happen

00:04:14.002 --> 00:04:15.652
if we go to the top of a mountain

00:04:15.652 --> 00:04:17.874
where the air pressure is lower,

00:04:17.874 --> 00:04:19.726
we have just fewer air
molecules in general.

00:04:19.726 --> 00:04:22.386
That means we're also going to
have lower oxygen molecules.

00:04:22.386 --> 00:04:24.439
So we could say that the
partial pressure of oxygen

00:04:24.439 --> 00:04:26.089
is going to be lower.

00:04:26.089 --> 00:04:28.667
So we could say, partial pressure

00:04:28.667 --> 00:04:31.258
of reactant will be lower.

00:04:31.258 --> 00:04:32.675
Partial pressure.

00:04:34.491 --> 00:04:36.823
There's just going to be fewer
oxygen molecules from the air

00:04:36.823 --> 00:04:39.987
being able to bump and react
with the zinc molecules.

00:04:39.987 --> 00:04:41.604
Well, actually, it's not
reacting with the zinc molecules,

00:04:41.604 --> 00:04:44.441
as we saw in the original reactions,

00:04:44.441 --> 00:04:45.855
when we look at the half reactions.

00:04:45.855 --> 00:04:49.980
Fewer reactions from the air
just bumping in the right way

00:04:49.980 --> 00:04:54.173
with the water molecules
and actually the electrons

00:04:54.173 --> 00:04:56.659
that are coming in through the circuit,

00:04:56.659 --> 00:04:57.838
you're just going to have fewer of them

00:04:57.838 --> 00:05:01.137
bouncing around, being
able to do this reaction.

00:05:01.137 --> 00:05:04.673
So you could say partial pressure,

00:05:04.673 --> 00:05:07.089
partial pressure of reactant.

00:05:09.992 --> 00:05:11.507
Or maybe I'll say partial pressure,

00:05:11.507 --> 00:05:13.343
or you could also do the
concentration of the reaction,

00:05:13.343 --> 00:05:14.676
there's going to be just, reactant.

00:05:14.676 --> 00:05:16.242
There's going to be less of it around.

00:05:16.242 --> 00:05:20.148
Partial pressure or we
can say concentration,

00:05:20.148 --> 00:05:21.815
concentration lower,

00:05:24.626 --> 00:05:25.459
lower,

00:05:26.747 --> 00:05:27.580
so lower,

00:05:30.695 --> 00:05:33.018
so lower cell potential.

00:05:33.018 --> 00:05:33.935
Lower cell,

00:05:35.864 --> 00:05:36.698
cell potential.

00:05:36.698 --> 00:05:38.315
So actually, I just did it in reverse.

00:05:38.315 --> 00:05:39.839
I answered part two first.

00:05:39.839 --> 00:05:42.517
And so part one is lower.

00:05:42.517 --> 00:05:45.075
So we're gonna have a
lower cell potential.

00:05:45.075 --> 00:05:46.825
Lower cell potential.

00:05:49.890 --> 00:05:51.573
It's really important to get
the conceptual understanding

00:05:51.573 --> 00:05:52.509
of why it's happening.

00:05:52.509 --> 00:05:54.597
Remember, when we look
at the half reaction,

00:05:54.597 --> 00:05:55.876
what's happening,

00:05:55.876 --> 00:05:58.637
what is happening at our cathode,

00:05:58.637 --> 00:06:01.263
we have oxygen coming in from the air,

00:06:01.263 --> 00:06:04.866
and it gets into the kind of
pores of this porous substance,

00:06:04.866 --> 00:06:08.502
and when the oxygen,
the O_2 molecules bump

00:06:08.502 --> 00:06:11.128
in just the right way with the water

00:06:11.128 --> 00:06:12.710
and the electrons coming in,

00:06:12.710 --> 00:06:15.337
they just kind of go together, and react,

00:06:15.337 --> 00:06:16.885
you get your hydroxide,

00:06:16.885 --> 00:06:18.535
for they react to form the hydroxide.

00:06:18.535 --> 00:06:20.050
Now if you have less, you know,

00:06:20.050 --> 00:06:22.508
at a lower elevation, you're
gonna have a lot of oxygen.

00:06:22.508 --> 00:06:24.326
You're gonna have a high partial pressure

00:06:24.326 --> 00:06:26.447
of the molecular oxygen.

00:06:26.447 --> 00:06:28.203
So there are a lot of them
(mumbles) moment in time

00:06:28.203 --> 00:06:31.444
are going to be available
to bounce around and react.

00:06:31.444 --> 00:06:33.296
But if you go to a higher elevation,

00:06:33.296 --> 00:06:36.056
you're just gonna have
fewer of these characters.

00:06:36.056 --> 00:06:39.491
So you're gonna have
fewer of these characters.

00:06:39.491 --> 00:06:41.848
So you're going to have a lower
partial pressure of oxygen,

00:06:41.848 --> 00:06:43.154
or you could think of
it as you have a lower

00:06:43.154 --> 00:06:46.125
concentration of oxygen inside the pores,

00:06:46.125 --> 00:06:50.713
so it's gonna be harder for
this reaction to move forward.

00:06:50.713 --> 00:06:52.363
And you can think about
the extreme situation.

00:06:52.363 --> 00:06:54.232
What if you were going to
a super high elevation.

00:06:54.232 --> 00:06:55.747
If you were eventually going into space,

00:06:55.747 --> 00:06:57.027
where you have very little oxygen

00:06:57.027 --> 00:06:58.835
or no oxygen at all, well then,

00:06:58.835 --> 00:07:01.767
then the reaction's
going to stop altogether.

00:07:01.767 --> 00:07:04.835
So hopefully, hopefully that,

00:07:04.835 --> 00:07:07.636
that makes, let me just
go back to part c here.

00:07:07.636 --> 00:07:10.159
I'm having trouble with my, oh,

00:07:10.159 --> 00:07:12.986
this, then I go back to part c.

00:07:12.986 --> 00:07:14.403
And there you go.


2015 AP Chemistry free response 1a

WEBVTT
Kind: captions
Language: en

00:00:00.310 --> 00:00:03.091
- [Voiceover] Metal-air cells
are a relatively new type

00:00:03.091 --> 00:00:06.754
of portable energy source
consisting of a metal anode,

00:00:06.754 --> 00:00:10.133
an alkaline electrolyte
paste that contains water

00:00:10.133 --> 00:00:13.435
and a porous cathode
membrane that lets in oxygen

00:00:13.435 --> 00:00:14.845
from the air.

00:00:14.845 --> 00:00:17.765
A schematic of the cell is
shown above, and so we see

00:00:17.765 --> 00:00:19.205
the different parts right over here,

00:00:19.205 --> 00:00:21.407
we see the metal anode, it's an anode.

00:00:21.407 --> 00:00:24.407
So this would be the negative
terminal of our power source.

00:00:24.407 --> 00:00:26.687
It'll be the source of electrons.

00:00:26.687 --> 00:00:30.437
We have an alkaline electrolyte
paste that contains water.

00:00:30.437 --> 00:00:31.827
Let me underline that,
there's a lot of interesting

00:00:31.827 --> 00:00:32.877
words there.

00:00:32.877 --> 00:00:36.447
Alkaline electrolyte
paste that contains water.

00:00:36.447 --> 00:00:38.427
That's this right over here in the middle.

00:00:38.427 --> 00:00:40.047
When they say it's alkaline,

00:00:40.047 --> 00:00:42.807
that means that it's going
to be basic versus acidic.

00:00:42.807 --> 00:00:45.205
It's going to have a pH higher than seven.

00:00:45.205 --> 00:00:46.947
Electrolyte paste.

00:00:46.947 --> 00:00:48.867
An electrolyte is something
that if you dissolve it

00:00:48.867 --> 00:00:51.807
in a polar substance, a
polar substance like water,

00:00:51.807 --> 00:00:53.817
well then the solution is going to be good

00:00:53.817 --> 00:00:55.497
at conducting electricity.

00:00:55.497 --> 00:00:57.447
So what they tell us,
this electrolyte paste

00:00:57.447 --> 00:01:00.327
is gonna be something that's
good at conducting electricity,

00:01:00.327 --> 00:01:03.657
and they tell us it's alkaline,
so it's going to be basic.

00:01:03.657 --> 00:01:06.147
It's going to have a pH higher than seven.

00:01:06.147 --> 00:01:09.417
And a porous cathode
membrane that let's in oxygen

00:01:09.417 --> 00:01:10.557
from the air.

00:01:10.557 --> 00:01:12.097
So this is the cathode,
this is going to be

00:01:12.097 --> 00:01:13.359
the positive terminal.

00:01:13.359 --> 00:01:16.209
This is where the electrons
are going to be attracted to,

00:01:16.209 --> 00:01:19.509
and it's a porous cathode
membrane that lets in oxygen

00:01:19.509 --> 00:01:20.133
from the air.

00:01:20.133 --> 00:01:22.293
And so you can see that
oxygen is available

00:01:22.293 --> 00:01:23.763
in this membrane.

00:01:23.763 --> 00:01:26.789
It somehow is allowed to seep in

00:01:26.789 --> 00:01:29.111
because it is porous.

00:01:29.111 --> 00:01:32.411
Reduction potentials for the
cathode and three possible

00:01:32.411 --> 00:01:35.949
metal anodes are given in the table below.

00:01:35.949 --> 00:01:38.049
So remember, reduction potentials,

00:01:38.049 --> 00:01:38.989
you can view these.

00:01:38.989 --> 00:01:42.501
Reduction is the gaining

00:01:42.501 --> 00:01:43.761
of electrons.

00:01:43.761 --> 00:01:47.151
So this is the potential
to gain electrons,

00:01:47.151 --> 00:01:48.109
is one way to think about it,

00:01:48.109 --> 00:01:50.349
or a reaction that
somehow involves electrons

00:01:50.349 --> 00:01:52.871
being incorporated in some way.

00:01:52.871 --> 00:01:55.841
And right over here you
have molecular oxygen

00:01:55.841 --> 00:01:57.971
reacting with water.

00:01:57.971 --> 00:02:00.551
For every molecule of molecular oxygen,

00:02:00.551 --> 00:02:02.199
you get two molecules of water.

00:02:02.199 --> 00:02:05.831
Four electrons, and
then they react to form

00:02:05.831 --> 00:02:08.109
four hydroxide anions.

00:02:08.109 --> 00:02:10.241
So once again, this is
a reduction reaction

00:02:10.241 --> 00:02:12.911
because those electrons
are being incorporated

00:02:12.911 --> 00:02:15.491
into the molecule.

00:02:15.491 --> 00:02:17.921
And so you're left with the
hydroxide right over here.

00:02:17.921 --> 00:02:20.951
And if you look at our
metal air cell up here,

00:02:20.951 --> 00:02:22.961
where is that occurring?

00:02:22.961 --> 00:02:25.181
Well, you need oxygen, you need water

00:02:25.181 --> 00:02:26.531
and you need electrons.

00:02:26.531 --> 00:02:28.553
Well, if you look at the
cathode right over here,

00:02:28.553 --> 00:02:29.963
you got your electrons coming in,

00:02:29.963 --> 00:02:32.901
you got your oxygen coming
in, and water, we can assume,

00:02:32.901 --> 00:02:34.493
is available in this area.

00:02:34.493 --> 00:02:36.463
The electrolyte paste has water in it.

00:02:36.463 --> 00:02:38.639
The cathode is porous,

00:02:38.639 --> 00:02:40.949
it's a porous membrane-type substance.

00:02:40.949 --> 00:02:42.479
So they're all available over here.

00:02:42.479 --> 00:02:44.459
So you can assume that, that reaction

00:02:44.459 --> 00:02:47.489
could happen right over
here in the cathode.

00:02:47.489 --> 00:02:51.903
So let me just write it, 02 in as a gas.

00:02:51.903 --> 00:02:54.993
So for every molecule of O2,
you're gonna have two molecules

00:02:54.993 --> 00:02:59.307
of H2O in a liquid form.

00:02:59.307 --> 00:03:02.519
And then you got your electrons
coming in on the wire,

00:03:02.519 --> 00:03:05.819
I guess you could say,
and that is going to yield

00:03:05.819 --> 00:03:09.371
four hydroxide anions.

00:03:09.371 --> 00:03:11.261
Four hydroxide anions.

00:03:11.261 --> 00:03:13.149
And they're in a solution.

00:03:13.149 --> 00:03:16.271
They're part of that electrolyte
paste that's in water.

00:03:16.271 --> 00:03:18.579
They're an aqueous solution,
a water-based solution.

00:03:18.579 --> 00:03:20.499
And so that's going to
happen right over there

00:03:20.499 --> 00:03:22.781
so the hydroxide anions,

00:03:22.781 --> 00:03:24.761
I can even say four hydroxide anions

00:03:24.761 --> 00:03:27.489
are going to be produced
every time this reaction

00:03:27.489 --> 00:03:28.481
is happening.

00:03:28.481 --> 00:03:30.041
And they tell us the reduction potential.

00:03:30.041 --> 00:03:33.401
This has a positive potential,
has a positive voltage.

00:03:33.401 --> 00:03:36.491
And notice they say the
reduction potential at pH 11.

00:03:36.491 --> 00:03:41.291
So that's consistent
with alkaline conditions

00:03:41.291 --> 00:03:44.021
because this paste might seep
in through here a little bit

00:03:44.021 --> 00:03:46.541
and obviously you have all
this hydroxide being produced.

00:03:46.541 --> 00:03:50.021
So you're gonna have a
higher pH, a more basic pH.

00:03:50.021 --> 00:03:53.741
And so the fact that this
is a positive voltage,

00:03:53.741 --> 00:03:57.971
so plus 0.34 volts

00:03:57.971 --> 00:04:01.841
means that the potential
is going in this direction.

00:04:01.841 --> 00:04:04.871
The electric potential favors
this reaction to happen

00:04:04.871 --> 00:04:07.031
going from left to right.

00:04:07.031 --> 00:04:09.911
Now they also said they give
us the reduction potentials

00:04:09.911 --> 00:04:12.521
for the cathode, which
we just talked about,

00:04:12.521 --> 00:04:15.011
this is the reduction
potential for the cathode,

00:04:15.011 --> 00:04:17.141
and three possible metal anodes are given

00:04:17.141 --> 00:04:18.070
in the table below.

00:04:18.070 --> 00:04:21.044
So here there are three
possible metal anodes.

00:04:21.044 --> 00:04:23.725
So we could have zinc,
we could have sodium,

00:04:23.725 --> 00:04:26.759
we could have calcium,

00:04:26.759 --> 00:04:28.559
and so let's just go with
zinc since it's the first one

00:04:28.559 --> 00:04:29.027
listed here.

00:04:29.027 --> 00:04:32.697
So if we assumed that
the metal here was zinc,

00:04:32.697 --> 00:04:34.453
what's going to be going on?

00:04:34.453 --> 00:04:36.403
Well, you're going to
have the zinc reacting

00:04:36.403 --> 00:04:38.623
with these hydroxides
that are being produced

00:04:38.623 --> 00:04:41.413
over in the cathode, and
then you're going to use that

00:04:41.413 --> 00:04:44.533
to produce zinc oxide water and electrons.

00:04:44.533 --> 00:04:47.953
So you're actually gonna have
the reverse of this reaction.

00:04:47.953 --> 00:04:50.203
You're going to have,
let me write the reverse.

00:04:50.203 --> 00:04:53.713
You're going to have
zinc in the solid state.

00:04:53.713 --> 00:04:56.893
This whole anode is
made out of metal zinc.

00:04:56.893 --> 00:04:58.663
And then for every molecule of that,

00:04:58.663 --> 00:05:03.313
you're gonna have two hydroxide
anions that are dissolved

00:05:03.313 --> 00:05:04.568
in water.

00:05:04.568 --> 00:05:08.168
That's what makes the
electrolyte paste alkaline.

00:05:08.168 --> 00:05:12.098
And you are going to then go to,

00:05:12.098 --> 00:05:16.448
they're going to react and
you're going to form zinc oxide.

00:05:16.448 --> 00:05:19.688
Zinc oxide in the solid state,

00:05:19.688 --> 00:05:22.686
plus water

00:05:22.686 --> 00:05:24.218
in the liquid state,

00:05:24.218 --> 00:05:28.138
plus two, plus two electrons.

00:05:28.138 --> 00:05:31.460
And so this reaction
that I just described,

00:05:31.460 --> 00:05:33.801
this is going to be
happening right over here.

00:05:33.801 --> 00:05:35.600
So you could think of it
as the hydroxide anions

00:05:35.600 --> 00:05:38.480
get formed at the cathode,
and then they move their way

00:05:38.480 --> 00:05:41.960
over to the left to the anode
where they react with the zinc

00:05:41.960 --> 00:05:45.890
and they turn, or the zinc
reacts and forms zinc oxide,

00:05:45.890 --> 00:05:48.408
so you have more and more
zinc oxide being formed,

00:05:48.408 --> 00:05:50.930
water, which can then
seep its way back into

00:05:50.930 --> 00:05:53.358
the electrolyte paste and
then it can eventually

00:05:53.358 --> 00:05:55.040
react again at the cathode,

00:05:55.040 --> 00:05:56.330
and then you have these two electrons.

00:05:56.330 --> 00:05:58.938
So these electrons, this
turns into an electron source

00:05:58.938 --> 00:06:01.158
right over here, and then
the electrons would migrate

00:06:01.158 --> 00:06:03.770
and then they can go to the
positive side, the cathode,

00:06:03.770 --> 00:06:05.240
to react again.

00:06:05.240 --> 00:06:07.250
And so you can start
to see how this will be

00:06:07.250 --> 00:06:09.980
an energy source that you
can tap into this current

00:06:09.980 --> 00:06:14.060
that'll form to do some useful work.

00:06:14.060 --> 00:06:16.400
That's why you have an energy source.

00:06:16.400 --> 00:06:18.072
All right, so let's
read that questions now

00:06:18.072 --> 00:06:21.152
that we have a decent
understanding of what's going on.

00:06:21.152 --> 00:06:24.766
Early forms of metal air
cells use zinc as the anode.

00:06:24.766 --> 00:06:26.837
Well, that's the example
we just thought about.

00:06:26.837 --> 00:06:29.357
Zinc oxide is produced
as the cell operates

00:06:29.357 --> 00:06:33.717
according to the overall equation below.

00:06:33.717 --> 00:06:35.914
For every two molecules of zinc

00:06:35.914 --> 00:06:38.104
and one molecule of molecular oxygen,

00:06:38.104 --> 00:06:41.434
you produce two molecules of zinc oxide.

00:06:41.434 --> 00:06:43.156
Use the data in the table above,

00:06:43.156 --> 00:06:46.876
calculate the cell potential
for the zinc air cell.

00:06:46.876 --> 00:06:49.004
So let's think about, let's
break down this reaction.

00:06:49.004 --> 00:06:50.830
Actually, we can just break it down

00:06:50.830 --> 00:06:54.100
into these two steps here.

00:06:54.100 --> 00:06:57.010
Because notice, this is,

00:06:57.010 --> 00:06:59.184
we can't see them both at the same time

00:06:59.184 --> 00:07:03.322
but this, the things that are reacting,

00:07:03.322 --> 00:07:05.244
you have zinc.

00:07:05.244 --> 00:07:06.948
Let me underlie the
things that are reacting.

00:07:06.948 --> 00:07:09.708
You have zinc, you have zinc.

00:07:09.708 --> 00:07:13.546
You have oxygen, you have oxygen.

00:07:13.546 --> 00:07:15.378
And so if you return this,

00:07:15.378 --> 00:07:17.028
if you return the second reaction around

00:07:17.028 --> 00:07:19.039
like we did before, and let me rewrite it,

00:07:19.039 --> 00:07:22.072
let me rewrite both of them
actually a little bit lower

00:07:22.072 --> 00:07:23.512
right over here.

00:07:23.512 --> 00:07:26.031
So you have this top reaction.

00:07:26.031 --> 00:07:31.031
So you have O2 gaseous state plus two

00:07:31.133 --> 00:07:35.993
H2O liquid, plus four electrons.

00:07:35.993 --> 00:07:38.573
Whoops, four electrons,

00:07:38.573 --> 00:07:42.263
yields four hydroxide anions

00:07:42.263 --> 00:07:44.363
in aqueous solution.

00:07:44.363 --> 00:07:45.695
And then this one, we said we're gonna go

00:07:45.695 --> 00:07:47.255
in the other direction.

00:07:47.255 --> 00:07:49.535
So you're going to have zinc,

00:07:49.535 --> 00:07:52.445
you're going to have zinc

00:07:52.445 --> 00:07:54.063
in the solid state,

00:07:54.063 --> 00:07:58.235
plus two hydroxide anions.

00:07:58.235 --> 00:08:02.345
And then that's going to yield zinc,

00:08:02.345 --> 00:08:04.865
zinc oxide in the solid state,

00:08:04.865 --> 00:08:07.895
plus liquid water

00:08:07.895 --> 00:08:09.995
plus two electrons.

00:08:09.995 --> 00:08:14.015
So when you see this, you
see that we are reacting,

00:08:14.015 --> 00:08:16.415
we have the oxygen, we have the zinc,

00:08:16.415 --> 00:08:18.215
which are the two things
(mumbles) interact here.

00:08:18.215 --> 00:08:19.865
And if you want to make them equivalent

00:08:19.865 --> 00:08:20.987
in terms of the number of molecules,

00:08:20.987 --> 00:08:22.095
we could say all right,

00:08:22.095 --> 00:08:24.467
we have one molecule of molecular oxygen

00:08:24.467 --> 00:08:25.787
and we need two zincs.

00:08:25.787 --> 00:08:28.727
So let me multiply this
whole reaction by two.

00:08:28.727 --> 00:08:32.327
So two zincs react with four hydroxides,

00:08:32.327 --> 00:08:35.537
react to produce two zinc oxides,

00:08:35.537 --> 00:08:38.447
two molecules of water,

00:08:38.447 --> 00:08:40.457
two molecules of water,

00:08:40.457 --> 00:08:42.016
and then four electrons.

00:08:42.016 --> 00:08:43.937
I just said, well, if this
reaction happened twice,

00:08:43.937 --> 00:08:46.347
you'd would have just twice
as many of the reactants

00:08:46.347 --> 00:08:48.039
and the products here.

00:08:48.039 --> 00:08:51.761
And then notice, now you have

00:08:51.761 --> 00:08:53.412
a molecule of molecular oxygen,

00:08:53.412 --> 00:08:55.331
two molecules of zinc,

00:08:55.331 --> 00:08:57.881
molecule of molecular oxygen,
two molecules of zinc.

00:08:57.881 --> 00:08:59.801
If all of this were to happen,

00:08:59.801 --> 00:09:03.639
you are going to produce
two molecules of zinc oxide.

00:09:03.639 --> 00:09:06.101
And well, what about
everything else that I put,

00:09:06.101 --> 00:09:07.721
that were in these reactions?

00:09:07.721 --> 00:09:09.611
Well, the water is here,

00:09:09.611 --> 00:09:11.981
but then water also gets
two modules of water,

00:09:11.981 --> 00:09:13.151
two molecules of water.

00:09:13.151 --> 00:09:15.281
So I guess if you look
at the total reaction,

00:09:15.281 --> 00:09:19.091
we're neutral there, we haven't
produced or lost any water.

00:09:19.091 --> 00:09:22.631
You have four electrons,
you have four electrons.

00:09:22.631 --> 00:09:23.684
So that's why they didn't write it

00:09:23.684 --> 00:09:25.497
in this total reaction here.

00:09:25.497 --> 00:09:28.770
And these four hydroxide
molecules, anions,

00:09:28.770 --> 00:09:30.839
well, they're going to be
used up in this second part

00:09:30.839 --> 00:09:31.857
of the reactions.

00:09:31.857 --> 00:09:32.617
So we're neutral there.

00:09:32.617 --> 00:09:34.509
They get produced, but then they get used.

00:09:34.509 --> 00:09:35.649
So if you look at the total reaction,

00:09:35.649 --> 00:09:39.009
you're using the molecular
oxygen and the zinc

00:09:39.009 --> 00:09:41.499
to produce zinc oxide.

00:09:41.499 --> 00:09:43.479
And so they say use the
data in the table above,

00:09:43.479 --> 00:09:46.957
calculate the cell potential
for the zinc-air cell.

00:09:46.957 --> 00:09:50.479
Well, the potential for
this top reaction is zero,

00:09:50.479 --> 00:09:55.447
is positive .34 volts.

00:09:55.447 --> 00:09:57.219
And now what's the reaction,
what's the potential

00:09:57.219 --> 00:09:59.137
for this bottom reaction?

00:09:59.137 --> 00:10:01.059
Well, it's the reverse of this reaction,

00:10:01.059 --> 00:10:04.147
so this reaction has a negative potential,

00:10:04.147 --> 00:10:05.661
but since we reversed it, it's going to be

00:10:05.661 --> 00:10:07.131
a positive potential.

00:10:07.131 --> 00:10:11.331
So it's going to be positive 1.31 volts.

00:10:11.331 --> 00:10:12.514
Now some of you might be saying,

00:10:12.514 --> 00:10:15.244
well not only did we reverse
it, we multiplied it by two.

00:10:15.244 --> 00:10:17.374
We said two of those
reactions, wouldn't we multiply

00:10:17.374 --> 00:10:19.174
the voltage by two?

00:10:19.174 --> 00:10:20.924
Well, if we were just
talking about the energy

00:10:20.924 --> 00:10:23.147
released from a reaction,
well, yeah, absolutely.

00:10:23.147 --> 00:10:24.836
If you're gonna have the
reaction twice or twice as much

00:10:24.836 --> 00:10:26.068
of the reaction, you're
gonna have twice as much

00:10:26.068 --> 00:10:27.234
of the energy.

00:10:27.234 --> 00:10:28.824
But voltage, you have to remember,

00:10:28.824 --> 00:10:32.394
you can view it as potential
energy per unit charge.

00:10:32.394 --> 00:10:34.772
So since we're not, this isn't (mumbles)

00:10:34.772 --> 00:10:38.437
absolute energy, this is
your energy per unit charge

00:10:38.437 --> 00:10:39.907
is one way to think about it.

00:10:39.907 --> 00:10:41.197
When you're doing more of it,

00:10:41.197 --> 00:10:43.627
it doesn't change the actual voltage.

00:10:43.627 --> 00:10:45.397
So that's an important
thing to think about.

00:10:45.397 --> 00:10:47.735
If this was talking about
total energy or entropy

00:10:47.735 --> 00:10:50.225
or something like that,
then if you were to multiply

00:10:50.225 --> 00:10:53.257
both sides by two, you would
multiply the energy released

00:10:53.257 --> 00:10:54.757
or taken by two.

00:10:54.757 --> 00:10:56.047
But since we're talking about voltage,

00:10:56.047 --> 00:10:58.507
voltage isn't a quantity
that depends on the number

00:10:58.507 --> 00:11:00.937
of charges or the number of
molecules we're doing to,

00:11:00.937 --> 00:11:02.257
it's a per.

00:11:02.257 --> 00:11:04.777
It's what is the potential per unit charge

00:11:04.777 --> 00:11:06.427
is one way to think about it.

00:11:06.427 --> 00:11:09.035
And so for this whole
reaction, we would just add

00:11:09.035 --> 00:11:11.947
the combined voltage of both of these,

00:11:11.947 --> 00:11:13.565
and then you would get

00:11:13.565 --> 00:11:17.767
1.65,

00:11:17.767 --> 00:11:20.675
1.65 volts.

00:11:20.675 --> 00:11:22.057
Now let's do part two.

00:11:22.057 --> 00:11:26.057
The electrolyte paste
contains hydroxide ions.

00:11:26.057 --> 00:11:29.329
On the diagram of the
cell above, draw an arrow

00:11:29.329 --> 00:11:32.419
to indicate the direction of
migration of hydroxide ions

00:11:32.419 --> 00:11:34.997
through the electrolyte
as a cell operates.

00:11:34.997 --> 00:11:37.007
Well, we've already thought about that.

00:11:37.007 --> 00:11:39.889
The hydroxide gets produced at the cathode

00:11:39.889 --> 00:11:43.849
with this reaction, and then
it gets used up in the anode,

00:11:43.849 --> 00:11:48.319
so the hydroxide is going to be moving,

00:11:48.319 --> 00:11:50.479
the hydroxide is going to be moving

00:11:50.479 --> 00:11:53.222
in that direction.


Pronoun number

WEBVTT
Kind: captions
Language: en

00:00:00.394 --> 00:00:03.088
- [Voiceover] So here's
something weird and cool

00:00:03.088 --> 00:00:05.537
about English and languages in general.

00:00:05.537 --> 00:00:08.126
It's that they have a sense of number

00:00:08.126 --> 00:00:10.391
kind of encoded into them.

00:00:10.391 --> 00:00:13.046
We call this grammatical number.

00:00:14.446 --> 00:00:17.732
And the way this plays
out is in the difference

00:00:17.732 --> 00:00:21.888
between singular and plural in English.

00:00:21.888 --> 00:00:24.849
The idea of there being one of a thing

00:00:24.849 --> 00:00:27.889
or more than one of a thing.

00:00:31.069 --> 00:00:35.729
More than one of a thing.

00:00:35.729 --> 00:00:37.423
There we go.

00:00:37.423 --> 00:00:40.152
And this extends throughout the language

00:00:40.152 --> 00:00:42.009
and I want to talk about today,

00:00:42.009 --> 00:00:44.726
the way it applies to pronouns.

00:00:44.726 --> 00:00:49.726
So the singular form of me is me.

00:00:51.112 --> 00:00:52.470
Right, that's the singular form.

00:00:52.470 --> 00:00:54.932
The plural form of it, excuse me.

00:00:55.902 --> 00:00:59.646
The plural form of me is us.

00:01:01.416 --> 00:01:04.587
Because you know, there are many.

00:01:04.587 --> 00:01:07.224
Assuming, okay, assuming I was cloned.

00:01:07.224 --> 00:01:09.523
There's one of me, fine, that's singular.

00:01:09.523 --> 00:01:13.306
But let's say I walk into like
a cloning machine, you know,

00:01:13.306 --> 00:01:16.500
and it's like, a part of
it has got little bubbles

00:01:16.500 --> 00:01:18.985
and it's full of this
weird, viscous liquid.

00:01:18.985 --> 00:01:21.584
It shoots out another David.

00:01:21.584 --> 00:01:22.838
Suddenly there's two David's.

00:01:22.838 --> 00:01:23.965
May the earth tremble.

00:01:23.965 --> 00:01:26.463
But how do we refer to ourselves?

00:01:26.463 --> 00:01:29.386
More than one me is us.

00:01:29.386 --> 00:01:31.721
The grammatical number increases.

00:01:31.721 --> 00:01:33.729
I'm part of a group now.

00:01:33.729 --> 00:01:38.199
Or for a more normal
prosaic, non-cloning example,

00:01:38.199 --> 00:01:41.102
let's say my sister and I
are going out for coffee.

00:01:41.102 --> 00:01:43.747
I'd refer to the two of us together as us.

00:01:43.747 --> 00:01:47.572
That's the grammatical
number, it's plural.

00:01:47.572 --> 00:01:49.090
So it's important to remember

00:01:49.090 --> 00:01:51.354
when you are writing or speaking,

00:01:51.354 --> 00:01:54.628
to keep singular and plural straight

00:01:54.628 --> 00:01:56.312
throughout the course of a sentence

00:01:56.312 --> 00:01:58.030
or a paragraph because you don't want

00:01:58.030 --> 00:01:59.597
to mislead people into thinking

00:01:59.597 --> 00:02:01.478
you're talking about something else.

00:02:01.478 --> 00:02:04.392
Let me show you what I mean.

00:02:04.392 --> 00:02:09.392
For example, I would say
I looked at my watch.

00:02:12.252 --> 00:02:13.796
I don't have a watch anymore.

00:02:13.796 --> 00:02:14.632
Do you have watches?

00:02:14.632 --> 00:02:16.072
Do people still have watches?

00:02:16.072 --> 00:02:21.072
Now I wouldn't say, I looked at our watch,

00:02:24.756 --> 00:02:29.098
unless, I don't know, a
partner and I shared a watch.

00:02:29.098 --> 00:02:32.152
Unless my little sister and
I both had the same watch

00:02:32.152 --> 00:02:36.958
and we traded it back
and forth each month.

00:02:36.958 --> 00:02:39.153
Which is pretty unlikely
and kind of silly.

00:02:39.153 --> 00:02:41.509
And so what I'm trying to say is that

00:02:41.509 --> 00:02:46.509
"our" doesn't agree, doesn't
match up with "I" or "my."

00:02:46.896 --> 00:02:51.896
This is plural and this is singular.

00:02:52.609 --> 00:02:57.609
That is a very strange
place to wear a watch.

00:02:57.729 --> 00:02:58.994
What is that, at the elbow?

00:02:58.994 --> 00:03:01.351
Alright, so we've got
the dog wagged its tail.

00:03:01.351 --> 00:03:06.351
Dog is singular, its is singular.

00:03:07.411 --> 00:03:12.411
Want to make sure these things match up.

00:03:12.555 --> 00:03:16.850
We made our beds.

00:03:16.850 --> 00:03:20.774
This is plural and this is plural.

00:03:20.774 --> 00:03:25.774
As opposed to we made my beds.

00:03:26.336 --> 00:03:29.691
Which, who has multiple beds first of all.

00:03:29.691 --> 00:03:32.257
But it would also sound
like multiple people,

00:03:32.257 --> 00:03:37.257
including me, were assisting
me in making my many beds.

00:03:40.151 --> 00:03:42.995
There are two exceptions to this.

00:03:47.265 --> 00:03:50.145
And they are you and they.

00:03:51.665 --> 00:03:56.665
And either one can be singular or plural.

00:04:00.127 --> 00:04:02.527
So there can be a singular
you or a plural you.

00:04:02.527 --> 00:04:06.000
There can be a singular
they or a plural they.

00:04:06.000 --> 00:04:08.762
And I'll explain more
about singular they later.

00:04:08.762 --> 00:04:12.662
The important thing is
to be consistent overall.

00:04:16.702 --> 00:04:18.710
So if you establish that
something is singular,

00:04:18.710 --> 00:04:21.033
you need to maintain that singularity

00:04:21.033 --> 00:04:24.016
throughout the rest of
talking about that thing.

00:04:24.016 --> 00:04:26.826
So if I'm talking about cantaloupe,

00:04:26.826 --> 00:04:29.567
and here's a test, can I spell cantaloupe

00:04:29.567 --> 00:04:30.971
in real time without looking it up.

00:04:30.971 --> 00:04:32.050
That looks right to me.

00:04:32.050 --> 00:04:36.231
The cantaloupe was delicious.

00:04:36.231 --> 00:04:41.231
In the next sentence, I would
say I ate it in one sitting.

00:04:46.772 --> 00:04:48.827
And it's not I ate them, it's I ate it

00:04:48.827 --> 00:04:51.636
because there's only
one cantaloupe, you see?

00:04:51.636 --> 00:04:53.773
That's what I mean
about grammatical number

00:04:53.773 --> 00:04:55.766
and grammatical number agreement.

00:04:55.766 --> 00:04:59.447
You just want to make
sure that this thing,

00:04:59.447 --> 00:05:02.975
which we call an antecedent,
links up with a pronoun.

00:05:02.975 --> 00:05:05.786
So the thing you say
before you use the pronoun

00:05:05.786 --> 00:05:10.411
has to match up in terms of
whether it's singular or plural.

00:05:10.411 --> 00:05:11.612
You get that figured out, you will be

00:05:11.612 --> 00:05:13.341
a master of grammatical number.

00:05:13.341 --> 00:05:16.174
You can learn anything.

00:05:16.174 --> 00:05:17.725
David out.


Indefinite Pronouns

WEBVTT
Kind: captions
Language: en

00:00:00.702 --> 00:00:01.514
- [Voiceover] Hey grammarians,

00:00:01.514 --> 00:00:02.514
today I'm gonna talk about the idea

00:00:02.514 --> 00:00:04.650
of the indefinite pronoun,

00:00:04.650 --> 00:00:06.182
which looks kinda complicated

00:00:06.182 --> 00:00:08.598
but really just does
what it says on the tin.

00:00:08.598 --> 00:00:11.081
An indefinite pronoun is just that,

00:00:11.081 --> 00:00:15.562
it's indefinite, undefined, uncertain.

00:00:15.562 --> 00:00:16.793
These are pronouns that we use when

00:00:16.793 --> 00:00:18.947
we're not being especially specific.

00:00:19.789 --> 00:00:20.485
Words like

00:00:20.485 --> 00:00:25.485
any, anybody, each, everyone, nobody.

00:00:26.405 --> 00:00:27.801
Any time I need to remember

00:00:27.801 --> 00:00:30.284
what words fall into this category

00:00:30.284 --> 00:00:31.469
of indefinite pronouns,

00:00:31.469 --> 00:00:32.489
I just think of the song

00:00:32.489 --> 00:00:34.581
Everybody Needs Somebody to Love,

00:00:34.581 --> 00:00:35.692
originally by Solomon Burke,

00:00:35.692 --> 00:00:37.969
and then later made famous
by the Rolling Stones

00:00:37.969 --> 00:00:39.374
and the Blues Brothers.

00:00:39.374 --> 00:00:41.245
So a cool thing about indefinite pronouns,

00:00:41.245 --> 00:00:42.289
actually there are a couple.

00:00:42.289 --> 00:00:44.540
Number one, they can be used as both

00:00:44.540 --> 00:00:47.229
subject or object in a sentence.

00:00:48.372 --> 00:00:49.464
So if you said to me,

00:00:49.464 --> 00:00:51.167
"David, do you want pizza?"

00:00:51.167 --> 00:00:52.521
I could respond,

00:00:52.521 --> 00:00:54.689
"Yes, please! I'd love some,"

00:00:54.689 --> 00:00:56.959
using it as an object,

00:00:56.959 --> 00:00:59.051
or equally plausibly I could say,

00:00:59.051 --> 00:01:01.565
"Yes, please! Some would be great,"

00:01:01.565 --> 00:01:04.055
using it as a subject.

00:01:04.055 --> 00:01:06.043
Another really cool thing
about indefinite pronouns

00:01:06.043 --> 00:01:08.807
is that the words both,
neither, and either

00:01:08.807 --> 00:01:10.711
retain the dual.

00:01:10.711 --> 00:01:12.287
They are some of the only words in English

00:01:12.287 --> 00:01:15.069
that refer to only two things.

00:01:15.911 --> 00:01:17.283
So these three pronouns are actually

00:01:17.283 --> 00:01:18.883
a little bit less indefinite than

00:01:18.883 --> 00:01:21.927
most indefinite pronouns
because they refer to

00:01:21.927 --> 00:01:24.247
a set of two things.

00:01:24.247 --> 00:01:25.150
So if someone asks me,

00:01:25.150 --> 00:01:28.334
"Do you like mangoes or cherries more?"

00:01:28.334 --> 00:01:29.055
I could say,

00:01:29.055 --> 00:01:30.911
"I like both equally,"

00:01:30.911 --> 00:01:33.559
referring to the cherries and the mangoes

00:01:33.559 --> 00:01:34.998
at the same time.

00:01:34.998 --> 00:01:36.439
And this is really strange because,

00:01:36.439 --> 00:01:40.546
in English, this dual case
doesn't really exist anymore

00:01:40.546 --> 00:01:44.544
except for in very limited amounts

00:01:44.544 --> 00:01:46.398
because English distinguishes between

00:01:46.398 --> 00:01:48.278
whether or not there's one of something

00:01:48.278 --> 00:01:49.742
and more than one of something,

00:01:49.742 --> 00:01:52.342
but this is one of the very few cases

00:01:52.342 --> 00:01:53.922
where we ever distinguish between

00:01:53.922 --> 00:01:55.502
more than one of something

00:01:55.502 --> 00:01:58.162
and specifically two of something.

00:01:58.162 --> 00:01:59.738
There are not a whole
lot of words in English

00:01:59.738 --> 00:02:01.149
that refer to that,

00:02:01.149 --> 00:02:02.706
so I think that's really cool.

00:02:04.298 --> 00:02:07.072
The third cool thing about
indefinite pronouns is that

00:02:07.072 --> 00:02:10.532
they're usually treated
as singular, usually.

00:02:10.532 --> 00:02:13.131
So words like both, neither, and either

00:02:13.131 --> 00:02:15.616
are obviously plural but there are some

00:02:15.616 --> 00:02:17.538
that are a little bit fuzzier.

00:02:18.912 --> 00:02:20.052
For example, in this sentence,

00:02:20.052 --> 00:02:21.304
"Nobody was home,"

00:02:21.304 --> 00:02:24.110
we use the word was, the singular form.

00:02:24.971 --> 00:02:28.083
Even though that nobody could
refer to multiple people,

00:02:28.083 --> 00:02:30.493
or it's really referring
to the absence of anyone.

00:02:31.592 --> 00:02:32.915
Similarly, in this sentence

00:02:32.915 --> 00:02:34.935
"Everybody knows that I love onions,"

00:02:34.935 --> 00:02:36.931
we use the word knows, just like we'd say

00:02:36.931 --> 00:02:39.763
he knows, she knows, it knows.

00:02:39.763 --> 00:02:42.197
So that's the singular form of that verb.

00:02:43.411 --> 00:02:45.778
Even though the idea of everybody

00:02:45.778 --> 00:02:48.306
would seem to refer to
more than one person.

00:02:48.306 --> 00:02:50.538
The indefinite pronoun that we use

00:02:50.538 --> 00:02:53.439
to refer everybody usually conjugates

00:02:53.439 --> 00:02:58.038
the third person singular
form of verbs, usually.

00:02:58.038 --> 00:03:01.102
Let's get to one of the
weirder examples, though,

00:03:01.102 --> 00:03:03.030
because sometimes the context can

00:03:03.030 --> 00:03:04.958
carry you along into something that

00:03:04.958 --> 00:03:07.370
might seem a little quote, unquote

00:03:07.370 --> 00:03:09.717
"ungrammatical" but
really reflects the way

00:03:09.717 --> 00:03:12.153
that language is used today.

00:03:12.153 --> 00:03:12.989
And so although you might say

00:03:12.989 --> 00:03:15.661
"Everyone is looking at me,"

00:03:16.741 --> 00:03:19.990
here's an example from
Garner's Modern American Usage,

00:03:19.990 --> 00:03:21.845
which is one of the
several car-sized books

00:03:21.845 --> 00:03:25.514
I'm using to construct
this grammar course.

00:03:25.514 --> 00:03:29.185
"Everyone was crouched behind
furniture to surprise me,

00:03:29.185 --> 00:03:31.943
"but I already knew they were there."

00:03:33.109 --> 00:03:34.897
And you can see in the
beginning of this sentence,

00:03:34.897 --> 00:03:37.497
we say "Everyone was,"

00:03:37.497 --> 00:03:39.676
but then in the second
part of the sentence,

00:03:39.676 --> 00:03:41.812
we say "they were,"

00:03:41.812 --> 00:03:44.435
and we're using they to refer to everyone.

00:03:47.340 --> 00:03:48.292
So how can this be?

00:03:48.292 --> 00:03:49.935
This doesn't seem grammatical.

00:03:51.196 --> 00:03:52.936
But as Garner says,

00:03:52.936 --> 00:03:56.878
"Sometimes meaning rather than
grammar governs agreement."

00:03:58.579 --> 00:04:00.155
Is this grammatical?

00:04:00.155 --> 00:04:03.152
Yes, in that it makes sense.

00:04:03.152 --> 00:04:06.703
Does it adhere concretely
and in an iron-clad way

00:04:06.703 --> 00:04:08.472
to these rules that we've established?

00:04:08.472 --> 00:04:12.347
No, but language is kind
of messy in that way.

00:04:12.347 --> 00:04:14.691
Sometimes the meaning of the sentence,

00:04:14.691 --> 00:04:17.687
the fact that here everyone
refers to multiple people

00:04:17.687 --> 00:04:20.567
is going to override the rules

00:04:20.567 --> 00:04:22.611
that are previously established.

00:04:22.611 --> 00:04:23.747
And that's okay,

00:04:23.747 --> 00:04:25.369
as long as you're making sense.

00:04:26.371 --> 00:04:29.019
So relative pronouns are usually singular,

00:04:29.019 --> 00:04:33.314
unless the context drags them
into the realm of plural.

00:04:33.314 --> 00:04:34.663
So like their name implies,

00:04:34.663 --> 00:04:37.545
sometimes indefinite
pronouns can be a little...

00:04:37.545 --> 00:04:39.178
indefinite.

00:04:39.178 --> 00:04:40.479
Alright, here are the three cool things

00:04:40.479 --> 00:04:41.986
about indefinite pronouns.

00:04:41.986 --> 00:04:45.142
Number one, they can be
used as subjects or objects.

00:04:45.142 --> 00:04:48.602
Both, neither, and either
retain the dual form,

00:04:48.602 --> 00:04:49.485
which is super weird.

00:04:49.485 --> 00:04:52.806
And number three, indefinite
pronouns are usually

00:04:52.806 --> 00:04:54.817
treated as singular.

00:04:54.817 --> 00:04:56.098
Usually.

00:04:56.098 --> 00:04:57.118
I know that's confusing,

00:04:57.118 --> 00:04:58.490
but I have faith in you.

00:04:58.490 --> 00:05:00.177
You can learn anything.

00:05:00.177 --> 00:05:01.272
David, out.


Grammatical person and pronouns

WEBVTT
Kind: captions
Language: en

00:00:00.000 --> 00:00:02.249
- [Voiceover] Serious
question, grammarians.

00:00:02.249 --> 00:00:06.255
What's the difference between me and you?

00:00:06.255 --> 00:00:09.683
Well, in order to get, I mean
I don't mean that, you know,

00:00:09.683 --> 00:00:12.599
in a snarky way, I mean that
in like a conceptual way.

00:00:12.599 --> 00:00:15.339
What's the difference, in
terms of these two pronouns,

00:00:15.339 --> 00:00:16.442
what separates them?

00:00:16.442 --> 00:00:18.287
Well, one's about me and one's about you,

00:00:18.287 --> 00:00:21.387
but that seems kind of like
a pretty easy distinction

00:00:21.387 --> 00:00:23.606
that's right there on
the face of it, right.

00:00:24.626 --> 00:00:28.144
English, like other
languages, has this thing

00:00:28.144 --> 00:00:30.945
that grammarians call person.

00:00:30.945 --> 00:00:33.301
Obviously, we all know what a person is,

00:00:33.301 --> 00:00:36.785
it's a human being, but person
as a grammatical concept

00:00:36.785 --> 00:00:40.927
is a way of distinguishing between me,

00:00:40.927 --> 00:00:43.290
you and everybody else.

00:00:47.830 --> 00:00:51.664
In fact, we have special terms for this.

00:00:51.664 --> 00:00:56.664
So, any group containing
me is the first person.

00:00:57.540 --> 00:01:00.583
Any group containing you
is the second person,

00:01:00.583 --> 00:01:04.787
and everybody else falls
into the third person.

00:01:06.737 --> 00:01:10.676
So, whenever I talk about, you
know, third person singular,

00:01:10.676 --> 00:01:13.642
or first person plural,
all I'm really doing

00:01:13.642 --> 00:01:16.390
is going back to these
columns of, am I involved,

00:01:16.390 --> 00:01:18.463
are you involved, or is
everybody else involved?

00:01:19.453 --> 00:01:24.020
Right, so both me and us

00:01:24.020 --> 00:01:26.830
or I and we

00:01:26.830 --> 00:01:30.536
are first person pronouns,

00:01:30.536 --> 00:01:32.246
because they're about me

00:01:32.246 --> 00:01:34.503
or a group that contains me.

00:01:34.503 --> 00:01:37.899
Likewise, you is the second person.

00:01:37.899 --> 00:01:41.408
That's kind of it, both
singular and plural.

00:01:41.408 --> 00:01:46.308
Everybody else, that's
he, she, they, them,

00:01:46.308 --> 00:01:51.308
everybody, it, nothing,

00:01:53.082 --> 00:01:55.964
everything that is
neither me nor you falls

00:01:55.964 --> 00:01:58.801
into the everybody else
third person category.

00:01:58.801 --> 00:02:01.825
So, let's say you were giving someone

00:02:01.825 --> 00:02:04.508
advice in a kind of sideways way,

00:02:04.508 --> 00:02:09.508
like, one ought not to place

00:02:09.598 --> 00:02:14.138
one's hands

00:02:16.308 --> 00:02:18.008
on a hot stove.

00:02:22.608 --> 00:02:25.201
Alright, the temptation
might be, in some cases,

00:02:25.201 --> 00:02:27.872
you might forget what
pronoun you started out with.

00:02:27.872 --> 00:02:32.248
One is a third person pronoun

00:02:32.248 --> 00:02:34.398
and the temptation might

00:02:34.398 --> 00:02:36.700
sometimes be, you know,
you forget about it,

00:02:36.700 --> 00:02:39.030
sounds like you're
saying, a piece of advice,

00:02:39.030 --> 00:02:44.030
one ought not to place

00:02:44.139 --> 00:02:48.689
your hands

00:02:48.689 --> 00:02:52.569
on a hot stove.

00:02:53.669 --> 00:02:56.560
Well, you know, I mean this
is still not a good idea

00:02:56.560 --> 00:02:57.895
to put your hands on a hot stove,

00:02:57.895 --> 00:03:01.459
but you have to remember
which, what you're

00:03:01.459 --> 00:03:03.491
trying to connect here.

00:03:03.491 --> 00:03:05.314
This is a third person pronoun

00:03:05.314 --> 00:03:09.210
and this is a second person pronoun,

00:03:09.210 --> 00:03:11.271
and the two of them do not match up,

00:03:11.271 --> 00:03:13.760
they do not, as we say in grammar,

00:03:13.760 --> 00:03:17.650
agree, sad face.

00:03:17.650 --> 00:03:19.993
So, what you need to take care to do

00:03:19.993 --> 00:03:21.615
is to make sure that if
you're, if you start off

00:03:21.615 --> 00:03:23.577
talking about one, even if you're being

00:03:23.577 --> 00:03:26.051
kind of silly and pompous,
you've got to stick with one.

00:03:26.051 --> 00:03:28.932
If you start out talking about you,

00:03:28.932 --> 00:03:32.964
you got to stick with you,

00:03:32.964 --> 00:03:34.955
or I guess I could have
changed this back to one

00:03:34.955 --> 00:03:37.810
but I wanted to pop with the pink.

00:03:37.810 --> 00:03:41.564
Because if you don't do
this, then you run the risk

00:03:41.564 --> 00:03:45.766
of being confusing and unclear.

00:03:45.766 --> 00:03:47.459
So, you have to make sure that

00:03:47.459 --> 00:03:49.061
if you start off using
one grammatical person,

00:03:49.061 --> 00:03:51.417
you have to maintain use
of that grammatical person

00:03:51.417 --> 00:03:55.691
for as long as you're talking
about the same notion,

00:03:55.691 --> 00:03:57.867
the same idea, the same person.

00:03:57.867 --> 00:03:59.893
I used to take harmony singing classes

00:03:59.893 --> 00:04:02.720
at the Old Town School
of Folk Music in Chicago

00:04:02.720 --> 00:04:04.989
and I had this instructor
who said that the best way

00:04:04.989 --> 00:04:08.369
to sing harmony was to
remember to stay in your lane

00:04:13.229 --> 00:04:15.580
and I think that's a good way to conceive

00:04:15.580 --> 00:04:20.458
how to think about grammatical person

00:04:20.458 --> 00:04:23.615
is if you start in one lane,

00:04:25.665 --> 00:04:28.230
don't cross over by the
end of the sentence.

00:04:28.230 --> 00:04:32.198
Begin, begin your sentence in
the same lane as you started.

00:04:34.698 --> 00:04:38.055
You can learn anything, David out.


Emphatic pronouns

WEBVTT
Kind: captions
Language: en

00:00:00.722 --> 00:00:01.696
- [Voiceover] Alright, grammarians.

00:00:01.696 --> 00:00:03.309
So we know that there's one way

00:00:03.309 --> 00:00:06.105
to use this thing we
call reflexive pronouns

00:00:06.105 --> 00:00:08.877
and that's to say you're
doing something to yourself,

00:00:08.877 --> 00:00:09.814
as in the sentence

00:00:09.814 --> 00:00:14.294
I made myself breakfast.

00:00:14.294 --> 00:00:19.242
Right, I'm making myself breakfast.

00:00:20.142 --> 00:00:21.174
Or in the sentence

00:00:21.174 --> 00:00:26.074
Ronaldo cut himself shaving.

00:00:31.034 --> 00:00:35.294
Sorry about the capital S
there, that is a mistake.

00:00:35.294 --> 00:00:40.280
So Ronaldo and himself and I and myself.

00:00:40.280 --> 00:00:43.270
We use, these are called
reflexive pronouns

00:00:43.270 --> 00:00:45.467
and we use them when the subject

00:00:45.467 --> 00:00:48.999
and the object of a sentence
is the same thing, right,

00:00:48.999 --> 00:00:52.443
but there's another way to
use these reflexive pronouns

00:00:52.443 --> 00:00:55.227
and it's called emphatic usage.

00:00:55.227 --> 00:00:58.654
So I want you to imagine
me storming off in a huff

00:00:58.654 --> 00:01:01.210
or getting really excited
as I say the following:

00:01:01.210 --> 00:01:05.524
Well, if you won't help
me, I'll do it myself!

00:01:10.064 --> 00:01:13.936
Or, he's lying, I heard it myself.

00:01:18.176 --> 00:01:23.176
Or, the princess herself is
running the charity marathon.

00:01:27.697 --> 00:01:32.697
And what this is is what we
call emphatic or intensive

00:01:33.293 --> 00:01:37.055
because we use it to intensify a statement

00:01:37.055 --> 00:01:39.456
or to grant it emphasis, right?

00:01:39.456 --> 00:01:41.245
This is how it works.

00:01:41.245 --> 00:01:42.494
So instead of just saying...

00:01:42.494 --> 00:01:45.713
and the difference, the key
difference, between reflexive

00:01:45.713 --> 00:01:49.322
and intensive or emphatic
usage of this kind of pronoun

00:01:49.322 --> 00:01:53.546
is you could take these
right out of a sentence

00:01:53.546 --> 00:01:54.777
and it would still make sense.

00:01:54.777 --> 00:01:59.618
I'll do it, I heard it, the
princess will run the marathon.

00:01:59.618 --> 00:02:02.890
Right, we're using them as intensifiers

00:02:05.051 --> 00:02:05.661
which really means

00:02:05.661 --> 00:02:07.744
they can come right out.

00:02:07.744 --> 00:02:10.084
They're not essential to the
understanding of the sentence,

00:02:10.084 --> 00:02:13.698
you're just using these words

00:02:13.698 --> 00:02:16.712
in order to hammer home a point.

00:02:16.712 --> 00:02:19.158
You know, if someone
else isn't helping you

00:02:19.158 --> 00:02:21.097
you say I'll do it, but you wanna really

00:02:21.097 --> 00:02:22.197
hammer home the fact

00:02:22.197 --> 00:02:23.993
that you're going to be
doing it alone so you say

00:02:23.993 --> 00:02:27.236
I'll do it myself.

00:02:28.106 --> 00:02:30.822
And if you wanna emphasize
that you were there

00:02:30.822 --> 00:02:32.357
and you heard something
happen you would say

00:02:32.357 --> 00:02:35.296
I heard it myself.

00:02:35.296 --> 00:02:37.318
And if it's really crazy that

00:02:37.318 --> 00:02:40.806
the princess is running this
marathon then you would say

00:02:40.806 --> 00:02:45.806
whoa, the princess herself
will be there, and that's nuts.

00:02:46.417 --> 00:02:49.386
And that's the intensive
or emphatic pronoun.

00:02:49.386 --> 00:02:51.578
That's how you use it.

00:02:51.578 --> 00:02:53.150
You can learn anything.

00:02:53.150 --> 00:02:54.104
David out.


Subject and object pronouns

WEBVTT
Kind: captions
Language: en

00:00:00.153 --> 00:00:01.901
- [Voiceover] All right,
so grammarians, I want to

00:00:01.901 --> 00:00:03.424
talk to you about the difference between

00:00:03.424 --> 00:00:05.903
subject and object pronouns, but before

00:00:05.903 --> 00:00:08.016
we do that, let's start off with a little

00:00:08.016 --> 00:00:12.323
primer on what subjects
and objects actually are,

00:00:12.323 --> 00:00:15.270
Just generally for our
grammatical purposes.

00:00:15.270 --> 00:00:18.703
In grammar, the subject is
the part of the sentence

00:00:18.703 --> 00:00:21.263
or clause that does a thing.

00:00:21.263 --> 00:00:24.331
The subject does a thing.

00:00:24.331 --> 00:00:26.403
The object, on the other hand, is the

00:00:26.403 --> 00:00:30.853
thing that is acted on,
has stuff done to it,

00:00:30.853 --> 00:00:35.853
so the object has stuff done to it.

00:00:38.094 --> 00:00:40.877
The subject acts, the
object is acted upon,

00:00:40.877 --> 00:00:43.397
let's give an example.

00:00:43.397 --> 00:00:48.397
In the sentence, Reina wrote an e-mail,

00:00:52.765 --> 00:00:55.447
the subject of the sentence,
the doer of the thing

00:00:55.447 --> 00:00:57.925
is Reina, right, as the subject.

00:00:57.925 --> 00:01:00.465
The thing she is doing
is writing an e-mail,

00:01:00.465 --> 00:01:02.883
so Reina wrote an e-mail.

00:01:02.883 --> 00:01:06.012
E-mail is the object of the verb wrote.

00:01:06.012 --> 00:01:09.201
It is the object of the sentence.

00:01:09.201 --> 00:01:11.660
Now, there are cases when a sentence

00:01:11.660 --> 00:01:14.118
doesn't have an object.

00:01:14.118 --> 00:01:16.577
For example, we could just say

00:01:16.577 --> 00:01:20.149
Reina wrote.

00:01:20.149 --> 00:01:22.018
It doesn't have an object, it's just

00:01:22.018 --> 00:01:25.086
Reina's the subject, and
then there is no object.

00:01:25.086 --> 00:01:27.748
This is what we call intransitive usage,

00:01:27.748 --> 00:01:31.283
but you don't need to write
that down or anything.

00:01:31.283 --> 00:01:34.554
Now, understanding the relationship

00:01:34.554 --> 00:01:37.317
between e-mail and Reina enables you

00:01:37.317 --> 00:01:41.279
to understand how subject
and object pronouns are used.

00:01:41.279 --> 00:01:45.891
When we're subbing out
these nouns for pronouns,

00:01:45.891 --> 00:01:48.431
we can figure out which
ones we have to use,

00:01:48.431 --> 00:01:50.320
because pronouns have different forms

00:01:50.320 --> 00:01:55.320
depending on whether or not
they are subjects or objects.

00:01:55.675 --> 00:01:58.697
Reina is a girl's name, and if
we know that Reina is a girl,

00:01:58.697 --> 00:02:03.086
we can refer to her as either she or her.

00:02:03.086 --> 00:02:06.987
These are two of the feminine pronouns.

00:02:06.987 --> 00:02:10.156
One of these is a subject,
and one of them is an object.

00:02:10.156 --> 00:02:15.156
She is the subject form,
and her is the object form.

00:02:16.527 --> 00:02:20.155
If we wanted to rewrite this sentence,

00:02:20.155 --> 00:02:23.528
speaking of Reina, we would say,

00:02:23.528 --> 00:02:28.528
she wrote an e-mail.

00:02:31.582 --> 00:02:36.582
Not, her wrote an e-mail, you see.

00:02:37.840 --> 00:02:42.840
Because her is the object pronoun,

00:02:43.712 --> 00:02:46.701
and therefore is the thing that,

00:02:46.701 --> 00:02:48.634
the object pronoun has stuff done to it,

00:02:48.634 --> 00:02:50.544
as opposed to the doer of things.

00:02:50.544 --> 00:02:53.274
She is the subject form, it's the doer.

00:02:53.274 --> 00:02:57.338
For e-mail it's easy, this
just becomes it in all cases.

00:02:57.338 --> 00:03:02.260
The subject form, and the
object form are the same.

00:03:03.758 --> 00:03:05.099
Let's do a couple more examples

00:03:05.099 --> 00:03:08.117
just to shore this up
so you see what I mean.

00:03:09.715 --> 00:03:14.715
I give her a present.

00:03:16.124 --> 00:03:20.095
Right now, I is the
subject, her is the object.

00:03:20.095 --> 00:03:24.504
Subject, object, but
what if we switched it?

00:03:24.504 --> 00:03:26.190
What would it look like then?

00:03:26.190 --> 00:03:28.831
Well it wouldn't be her give I a present,

00:03:28.831 --> 00:03:32.610
because since we're switching
the subject and the object,

00:03:32.610 --> 00:03:35.138
we're gonna be switching the
pronouns that we use too,

00:03:35.138 --> 00:03:40.138
so it would be, she gave me a present.

00:03:44.510 --> 00:03:48.123
Now, she is the

00:03:48.123 --> 00:03:52.206
subject form of her,

00:03:52.206 --> 00:03:55.791
and me is the subject, is
the object form, excuse me,

00:03:55.791 --> 00:03:58.682
me is the object form of I.

00:04:00.484 --> 00:04:03.377
Get a little period in there.

00:04:03.377 --> 00:04:07.388
Same thing with they and he.

00:04:07.388 --> 00:04:11.160
They showed

00:04:11.160 --> 00:04:15.832
him a guitar.

00:04:15.832 --> 00:04:17.674
Why not?

00:04:17.674 --> 00:04:22.674
They is the subject,
and him is the object.

00:04:24.284 --> 00:04:26.702
Let's give it the old switcheroo.

00:04:26.702 --> 00:04:30.347
He showed

00:04:30.347 --> 00:04:34.356
them a guitar.

00:04:35.772 --> 00:04:39.510
Now, we do the switcheroo, him becomes he,

00:04:39.510 --> 00:04:41.989
so we go from the object form which is him

00:04:41.989 --> 00:04:45.788
to the subject from which is he,

00:04:45.788 --> 00:04:49.547
and then they, the
subject form becomes them,

00:04:49.547 --> 00:04:51.845
the object form.

00:04:54.071 --> 00:04:57.363
Now when it comes to you and it,

00:04:57.363 --> 00:05:00.979
you're in luck, because
the subject and object

00:05:00.979 --> 00:05:05.185
forms of these are the same, so subject

00:05:05.185 --> 00:05:08.051
equals object,

00:05:08.051 --> 00:05:11.557
with you and it.

00:05:11.557 --> 00:05:14.267
I could say you give it a present

00:05:14.267 --> 00:05:18.746
just as easily as I could
say it gives you a present.

00:05:18.746 --> 00:05:21.408
I didn't realize I changed
this to the past tense.

00:05:21.408 --> 00:05:24.516
She gives me a present.

00:05:24.516 --> 00:05:26.955
There we go, that's better.

00:05:26.955 --> 00:05:28.722
That's the difference between a subject

00:05:28.722 --> 00:05:30.632
and an object pronoun.

00:05:30.632 --> 00:05:32.123
You can learn anything.

00:05:32.123 --> 00:05:33.555
David out.


What is a pronoun?

WEBVTT
Kind: captions
Language: en

00:00:00.572 --> 00:00:01.570
- [Voiceover] Hello grammarians.

00:00:01.570 --> 00:00:05.135
We're going to start talking
about pronouns today,

00:00:05.135 --> 00:00:06.922
and of course that
begins with the question,

00:00:06.922 --> 00:00:09.350
What are pronouns?

00:00:10.940 --> 00:00:15.096
Allow me to answer that question
by way of a demonstration.

00:00:15.096 --> 00:00:19.575
Emma laughed so hard, milk
came out of Emma's nose.

00:00:23.235 --> 00:00:25.859
Zach lifted the log.

00:00:25.859 --> 00:00:29.283
Zach found a worm under the log.

00:00:29.283 --> 00:00:31.663
So, these sentences don't have pronouns,

00:00:31.663 --> 00:00:34.960
but what they do have is repeated nouns.

00:00:34.960 --> 00:00:37.318
Here we have Emma and
then we say Emma's again,

00:00:37.318 --> 00:00:38.955
and then we say Zach and the log,

00:00:38.955 --> 00:00:42.519
and then we say Zach and the log.

00:00:42.519 --> 00:00:44.179
But, people are smart, right?

00:00:44.179 --> 00:00:46.478
We have relatively long attention spans,

00:00:46.478 --> 00:00:49.523
and so if we start off a
sentence talking about Emma,

00:00:49.523 --> 00:00:51.212
and we're pretty sure that
we're still talking about Emma,

00:00:51.212 --> 00:00:53.453
we don't need to say that name twice.

00:00:53.453 --> 00:00:55.996
We don't need to say
Emma and then Emma again.

00:00:55.996 --> 00:00:58.097
So, what a pronoun does is it allows you

00:00:58.097 --> 00:01:02.160
to take out the unnecessary noun

00:01:02.160 --> 00:01:04.994
when we're very certain we
know what we're talking about.

00:01:04.994 --> 00:01:07.339
So you don't have to say
Emma a million times,

00:01:07.339 --> 00:01:11.042
you can replace Emma with her.

00:01:11.042 --> 00:01:13.318
Same thing applies to
the second two sentences.

00:01:13.318 --> 00:01:15.941
We don't have to keep on
mentioning Zach and the log

00:01:15.941 --> 00:01:17.614
when we know what we're talking about.

00:01:17.614 --> 00:01:19.122
So the first sentence would still read

00:01:19.122 --> 00:01:20.795
Zach lifted the log,

00:01:20.795 --> 00:01:22.420
but then in the second sentence

00:01:22.420 --> 00:01:24.057
we can replace the name Zach,

00:01:24.057 --> 00:01:25.880
since we already know
who we're talking about,

00:01:25.880 --> 00:01:28.956
with the word he, and we can
replace this little phrase,

00:01:28.956 --> 00:01:33.519
the log, with it, since we know
we're talking about the log.

00:01:33.519 --> 00:01:38.519
Now, words like her and he
and it are all pronouns.

00:01:39.893 --> 00:01:41.472
So, what are pronouns?

00:01:41.472 --> 00:01:45.221
They are words that
stand in for other words.

00:01:45.221 --> 00:01:47.462
Now, obviously, her, he, and it

00:01:47.462 --> 00:01:49.680
are not the only pronouns in English,

00:01:49.680 --> 00:01:52.339
but for now I just want
you to think about the idea

00:01:52.339 --> 00:01:56.774
that a pronoun is a word that
stands in for another word.

00:01:56.774 --> 00:01:58.516
You can learn anything.

00:01:58.516 --> 00:01:59.630
David out.


Reflexive pronouns

WEBVTT
Kind: captions
Language: en

00:00:00.120 --> 00:00:01.153
- [Voiceover] Hello, grammarians.

00:00:01.153 --> 00:00:03.197
Let's talk about reflexive pronouns

00:00:03.197 --> 00:00:04.497
and just as a word of warning,

00:00:04.497 --> 00:00:06.795
this means I'm going to be
talking about myself a lot.

00:00:06.795 --> 00:00:08.294
What I mean is that, in English,

00:00:08.294 --> 00:00:09.721
we have this distinction between

00:00:09.721 --> 00:00:11.974
the personal pronoun, so for example, me,

00:00:11.974 --> 00:00:15.741
and its reflexive
pronoun, which is myself.

00:00:17.311 --> 00:00:20.472
And we use these pronouns
in very specific cases.

00:00:20.472 --> 00:00:21.633
So I'm gonna show you what all

00:00:21.633 --> 00:00:23.874
of those reflexive pronouns look like

00:00:23.874 --> 00:00:26.196
contrasted with their
personal pronoun forms

00:00:26.196 --> 00:00:28.320
and then we're going to
talk about how we use them.

00:00:28.320 --> 00:00:30.038
So in the first person we say

00:00:30.038 --> 00:00:32.233
the personal pronoun is me,

00:00:32.233 --> 00:00:35.322
the reflexive pronoun is myself.

00:00:35.322 --> 00:00:37.702
The first person plural
personal pronoun is us

00:00:37.702 --> 00:00:40.685
and the reflexive form
of that is ourselves.

00:00:40.685 --> 00:00:42.171
Then in the second person,

00:00:42.171 --> 00:00:46.212
both plural and singular
personal pronoun is you

00:00:46.212 --> 00:00:48.929
and then, in the reflexive
it can be either yourself

00:00:48.929 --> 00:00:50.589
when you're addressing one person

00:00:50.589 --> 00:00:53.747
or yourselves when the
"you" you are talking to

00:00:53.747 --> 00:00:55.407
consists of more than one person.

00:00:55.407 --> 00:00:58.297
The singular third person
pronouns look like this

00:00:58.297 --> 00:01:01.431
it, her, and him and
their reflective versions

00:01:01.431 --> 00:01:04.497
are as follows... itself,
herself, and himself.

00:01:04.497 --> 00:01:07.632
Finally, the personal pronoun them

00:01:07.632 --> 00:01:10.987
becomes the reflexive pronoun, themselves.

00:01:10.987 --> 00:01:13.890
Now, all of these are what we
would call object pronouns.

00:01:13.890 --> 00:01:15.748
They can all be the object of a verb.

00:01:15.748 --> 00:01:17.152
So they're never the do-ers,

00:01:17.152 --> 00:01:18.673
they're always the do-ees.

00:01:18.673 --> 00:01:20.971
With the exception of you or it,

00:01:20.971 --> 00:01:23.433
none of these pronouns can be

00:01:23.433 --> 00:01:25.836
the subject of a sentence.

00:01:25.836 --> 00:01:27.055
In Standard American English,

00:01:27.055 --> 00:01:29.112
it is not grammatical to say

00:01:29.112 --> 00:01:30.886
"Me eat a cookie" for example.

00:01:30.886 --> 00:01:33.163
It's part of why Cookie
Monster sounds so funny.

00:01:34.103 --> 00:01:35.473
So then the question becomes,

00:01:35.473 --> 00:01:37.830
when do you use these?

00:01:37.830 --> 00:01:39.478
So the place for these
object pronouns to go

00:01:39.478 --> 00:01:41.149
is in the back end of a sentence.

00:01:41.149 --> 00:01:42.613
what we call the predicate,

00:01:42.613 --> 00:01:45.260
where the object of the verb lives.

00:01:45.260 --> 00:01:47.292
So, for example, "She poked me."

00:01:47.292 --> 00:01:49.637
She is the subject of the sentence

00:01:49.637 --> 00:01:53.492
and me is the object, is the
object of the verb poked.

00:01:53.492 --> 00:01:56.255
It is the do-ee, it is
the thing that something

00:01:56.255 --> 00:01:57.892
is done to not the do-er.

00:01:57.892 --> 00:02:00.980
So that's when you'd use
object pronouns, generally.

00:02:00.980 --> 00:02:03.255
But, when do you use reflexive pronouns?

00:02:04.455 --> 00:02:06.739
You use reflexive
pronouns when the subject

00:02:06.739 --> 00:02:10.755
and the object of a
sentence are the same thing.

00:02:10.755 --> 00:02:12.793
Let me show you an example sentence.

00:02:13.762 --> 00:02:16.171
Janelle made herself breakfast.

00:02:17.803 --> 00:02:19.857
So in this sentence, herself and

00:02:19.857 --> 00:02:22.546
Janelle are the same person

00:02:23.956 --> 00:02:25.697
as opposed to the other
possibility which is

00:02:25.697 --> 00:02:27.824
Janelle making breakfast for someone else.

00:02:27.824 --> 00:02:29.985
Janelle made us breakfast,

00:02:29.985 --> 00:02:32.694
and in this case, this
usage is not reflective.

00:02:32.694 --> 00:02:35.935
She's not doing a thing
for herself or to herself.

00:02:35.935 --> 00:02:38.754
She's making breakfast for other people.

00:02:38.754 --> 00:02:41.367
And so, you'd just use the regular

00:02:41.367 --> 00:02:42.933
personal object pronoun there.

00:02:42.933 --> 00:02:45.373
You can only use the reflexive pronoun

00:02:45.373 --> 00:02:46.805
when the subject and the object

00:02:46.805 --> 00:02:49.000
of the sentence are the same thing.

00:02:49.000 --> 00:02:51.843
Janelle is the same thing as herself.

00:02:51.843 --> 00:02:53.620
Janelle is not the same thing as us,

00:02:53.620 --> 00:02:57.148
so we would say us here and not ourselves.

00:02:57.148 --> 00:02:58.240
How about this one?

00:02:58.240 --> 00:03:00.168
Roderick saw me in the mirror.

00:03:00.168 --> 00:03:02.060
Now I am not named Roderick.

00:03:02.060 --> 00:03:03.848
I am not the same thing as Roderick,

00:03:03.848 --> 00:03:06.066
and if I were writing a
sentence about myself,

00:03:06.066 --> 00:03:09.496
I would say, I saw myself in the mirror.

00:03:11.568 --> 00:03:14.924
Roderick and I, me, are
not the same person.

00:03:14.924 --> 00:03:18.128
I and myself are the same person.

00:03:18.128 --> 00:03:20.183
The same person as Roderick is Roderick.

00:03:20.183 --> 00:03:21.287
So if we were to say,

00:03:21.287 --> 00:03:22.843
Roderick saw Roderick in the mirror,

00:03:22.843 --> 00:03:24.085
we would render that as,

00:03:24.085 --> 00:03:27.398
Roderick saw himself

00:03:29.703 --> 00:03:33.001
because the subject
here and the object here

00:03:33.001 --> 00:03:34.443
are the same thing.

00:03:36.353 --> 00:03:37.928
So remember, you use reflexive pronouns

00:03:37.928 --> 00:03:39.610
when the subject and the object

00:03:39.610 --> 00:03:41.427
of a sentence are the same thing.

00:03:42.350 --> 00:03:44.069
It's really easy to get
tripped up this way,

00:03:44.069 --> 00:03:48.435
especially if there's a
compound object in the sentence.

00:03:48.435 --> 00:03:52.010
For example, you can
talk to Vidya or myself.

00:03:52.010 --> 00:03:53.473
I see this all the time,

00:03:53.473 --> 00:03:55.644
and in Standard American English

00:03:55.644 --> 00:03:57.247
this is not correct because you

00:03:57.247 --> 00:04:00.440
is not the same thing as me.

00:04:00.440 --> 00:04:01.960
And it's easy to get confused because

00:04:01.960 --> 00:04:04.328
you're talking about two people here

00:04:04.328 --> 00:04:08.264
in this object and that's
a little befuddling.

00:04:08.264 --> 00:04:09.623
It kind of throws you off.

00:04:09.623 --> 00:04:11.167
And so there's a test you can do.

00:04:11.167 --> 00:04:12.501
If you're unsure of whether or not

00:04:12.501 --> 00:04:14.104
it should be Vidya or myself or

00:04:14.104 --> 00:04:16.623
Vidya or me, which is what I would say,

00:04:16.623 --> 00:04:19.701
how do you tell?

00:04:19.701 --> 00:04:21.464
Take the other person out of the object,

00:04:21.464 --> 00:04:23.125
just for a little bit.

00:04:23.125 --> 00:04:25.180
So would you say, you can talk to myself

00:04:25.180 --> 00:04:27.804
or would you say, you can talk to me?

00:04:30.014 --> 00:04:31.449
Well, since we know you is not

00:04:31.449 --> 00:04:33.098
the same thing as myself,

00:04:33.098 --> 00:04:35.234
and you can only use reflexive pronouns

00:04:35.234 --> 00:04:38.717
when the subject and the
object are the same thing,

00:04:38.717 --> 00:04:40.736
the answer is me.

00:04:40.736 --> 00:04:42.153
So then, we bring Vidya back,

00:04:42.153 --> 00:04:43.815
we bring the other part
of the object back,

00:04:43.815 --> 00:04:46.554
and it becomes, you can
talk to Vidya or me.

00:04:48.804 --> 00:04:50.838
So when in doubt, sub it out.

00:04:50.838 --> 00:04:52.823
Take the other part of the object

00:04:52.823 --> 00:04:55.144
and just pretend it's not there

00:04:55.144 --> 00:04:57.164
and just think about how the subject

00:04:57.164 --> 00:04:58.757
and the object connect.

00:04:58.757 --> 00:05:00.555
Chances are, you won't actually end up

00:05:00.555 --> 00:05:02.284
using a reflexive pronoun.

00:05:02.284 --> 00:05:05.333
Perform that little check
and you'll never go wrong.

00:05:06.465 --> 00:05:08.492
You can learn anything. David out.


Relative pronouns

WEBVTT
Kind: captions
Language: en

00:00:00.000 --> 00:00:01.671
- [Voiceover] Grammarians,
we're gonna talk about

00:00:01.671 --> 00:00:04.434
relative pronouns today
and what relative pronouns

00:00:04.434 --> 00:00:06.594
do is they link clauses together,

00:00:06.594 --> 00:00:09.276
specifically, independent
and dependent clauses,

00:00:09.276 --> 00:00:11.714
and if you don't know what independent

00:00:11.714 --> 00:00:12.934
and dependent clauses are, that's okay,

00:00:12.934 --> 00:00:16.428
just, suffice it to say,
that these pronouns allow you

00:00:16.428 --> 00:00:19.182
to staple phrases together.

00:00:19.182 --> 00:00:22.238
For example, in the sentence,
the man who sold the world

00:00:22.238 --> 00:00:24.591
is coming by on Tuesday, the pronoun who,

00:00:24.591 --> 00:00:27.271
is the relative pronoun there,

00:00:27.271 --> 00:00:28.908
it's linking the independent clause,

00:00:28.908 --> 00:00:30.695
the man is coming by on Tuesday

00:00:30.695 --> 00:00:33.901
to the dependent clause, sold the world.

00:00:33.901 --> 00:00:38.475
The relative pronouns of
English are who, whom,

00:00:38.475 --> 00:00:42.747
whose, that and which, and we use them all

00:00:42.747 --> 00:00:44.984
for different things.

00:00:44.984 --> 00:00:47.972
So, we can use who, whom, whose and that

00:00:47.972 --> 00:00:52.232
to refer to people, and we can use

00:00:52.232 --> 00:00:57.158
whose, that and which to refer to things.

00:00:57.158 --> 00:00:59.551
Let me show you.

00:00:59.551 --> 00:01:03.477
You could say, the salad
that I bought was wilted.

00:01:03.477 --> 00:01:06.094
But at the same time, I can
also use that in this sentence.

00:01:06.094 --> 00:01:08.195
The man that I saw smiled.

00:01:08.195 --> 00:01:09.833
See, I'm using that to refer to him.

00:01:09.833 --> 00:01:12.689
I could also use who, but the word which,

00:01:12.689 --> 00:01:16.388
however, does not play
very nicely with people.

00:01:16.388 --> 00:01:19.493
In the sentence, the witch
who cast the spell is kind,

00:01:19.493 --> 00:01:22.975
we could use either the
witch who cast the spell

00:01:22.975 --> 00:01:25.450
or the witch that cast the spell because

00:01:25.450 --> 00:01:27.968
both that and who work with people.

00:01:27.968 --> 00:01:30.556
But which, strangely, does not.

00:01:30.556 --> 00:01:32.915
So we couldn't say, for example, the witch

00:01:32.915 --> 00:01:35.329
which owns a cat is cruel.

00:01:35.329 --> 00:01:38.056
That's just now how
the language shook out,

00:01:38.056 --> 00:01:42.731
which is not a relative
pronoun that applies to people.

00:01:44.851 --> 00:01:47.408
These are the relative
pronouns of English,

00:01:47.408 --> 00:01:49.263
this is broadly how
they work and I'm gonna

00:01:49.263 --> 00:01:52.467
get into more specifics
in following videos.

00:01:52.467 --> 00:01:54.825
You can learn anything, David out.