58306
I don't know if my question will be well received but I searched a pretty long
time and didn't found a good answer so I try.

I was trying to read this [NHK
article](https://www3.nhk.or.jp/news/html/20180424/k10011415381000.html?utm_int=netnewsup_contents_list-
items_005) and I found this form:

「いや、実はそもそも、みかんの出荷量が年々 **減ってきている**
んです。生産基盤が弱体化していて、このまま出荷量が減り続ければ値段が高い状態が続くこともあるかもしれません」

A this point,I searched why the てきている form is used and not simply てくる because
according to what I knew about てくる (an action that starts in the past and
continue in the future through now as explained in this
[post](https://japanese.stackexchange.com/a/677/25980) ),adding -ている was
useless since てくる contains by itself the notion of time that lasts a certain
time with the characteristics explained in the previous post)

So I tried to search but I only found posts that handle a small part of the
comparison(I didn't find all forms) and they are sometimes contradictory and
raise other questions (because sometimes like
[here](https://japanese.stackexchange.com/a/18659/25980) I find that てくる
starts in the present, but in the post that I gave before, the fact that it
started in the past is the only difference with ていく so if it's not the case,
it would mean that they are identical ?)

My question is: **What are the differences between the various forms of ていくand
てくる?**

(てform)いく

(てform)くる

(てform)いった

(てform)きた

(てform)いっている

(てform)きている

(てform)いっていた

(てform)きていた
CC BY-SA 4.0
2018-05-02T07:21:43.897
58295
2018-05-03T09:51:19.033
2018-05-02T07:29:05.817
25980
question
tense subsidiary-verbs aspect
A consistent explanation about the various forms of ていくand てくる?
How you understand them includes a couple of misconceptions, so please forget
about it for a while.

ていく and てくる have three usages (each of which is more frequent in this order).

  1. to do something and go somewhere/ come back
  2. to do something to an outward / inward direction
  3. something changes, repeats or accumulates gradually or step by step

As you see there's no "/" in the third usage, both ていく and てくる refer to the
exact same objective situation then. For example, 空が明るくなっていく and てくる mean "the
sky will get brighter and brighter". However, you can also say them when the
phenomenon is happening, where most English speakers will say "the sky is
getting brighter", which focuses on a slightly different point, though.

The difference is if the speaker is interested in the result. When you say
貧しくなっていった, it doesn't really tell how it went after, besides the person got
poorer and poorer. When you say 貧しくなってきた, however, it reflects the speaker's
sense of vulnerability and usually means the influence of the result remains
as it is.

**Their past form means either that the gradual change started or that the
action repeated in a certain period. 明るくなる or 貧しくなる are an example of the
gradual change.** (edit)

As you may know, た form doesn't only stand for past tense but also perfect
aspect. So, 空が明るくなってきた can mean something like "the sky has just started to
get brighter", which can be said in the same situation as "the sky is getting
brighter". That's why you may find it translated that way.

Thinking of "the sky is getting brighter", the focus of this sentence lies, I
believe, in the course of gradual change, which can be expressed with
明るくなってきている after all. Difference between 明るくなっていってる? Maybe "our sky" and
"their sky" then.

Edit: ている stands for either a progressive action or a remaining result.

When てきている means the former, the difference between てきた is relatively simple
and it focuses on how it's in the middle of continuous change, **while てきた
focuses on how the change started just before** (edit).

On the other hand, when it means the latter, the difference is subtle **in
examples of gradual change** (edit). If you take examples of repetitive
actions, as is often the case with this usage, it's like the below.

  * それまでやってきた: one ~~had~~ repeated something until then
  * 今までにやってきている: one ~~had~~ repeated something before and the result reflects in the current time (one has done it by now)
  * 今までやってきた: one has repeated something until the current time

てきていた is past tense of the above.

  * 暖かくなってきていたころ: when it was getting warm
  * 出会ったときにはすでに多くの成果を上げてきていた: He had already earned tons of successes when we first met.
CC BY-SA 4.0
2018-05-02T17:34:45.607
58306
2018-05-03T09:51:19.033
2018-05-03T09:51:19.033
4092
4092
58295
answer