33086
So what's the difference between asking:

だれか？

And:

だれが？
CC BY-SA 3.0
2016-03-23T14:25:46.547
33078
2016-03-23T17:23:14.970
13923
question
particles particle-が particle-か
What the difference between using か and が for a question?
In both cases you are missing a verb, so please keep in mind that any answer
assumes that the verb is being understood from context.

That being said, my reading of だれか？ would be to fill in with a verb that would
cause the first part to be interpreted as "someone?" such as in "is someone
there?".

My reading of だれが？would be closer to "who?" such as in "who did it?".

You may also refer to the definition from jisho.org of
[だれか](http://jisho.org/search/dareka) as someone/somebody.
CC BY-SA 3.0
2016-03-23T14:52:49.690
33080
2016-03-23T14:52:49.690
13806
33078
answer
Your question ultimately boils down to the difference between two particles: か
and が.

  * か is a question marker, and an indefinite marker. After an interrogative pronoun like だれ ( _"who"_ ), いつ ( _"when"_ ), or なに ( _"what"_ ), か forms the indefinite -- だれか ( _"*somewho"_ ⇒ _"someone"_ ), いつか ( _"*somewhen"_ ⇒ _"sometime"_ ), なにか ( _"*somewhat"_ ⇒ _"something"_ ).

  * が is mostly a subject marker (and sometimes, in archaic constructions, a kind of possessive linker between nouns). だれが would be _"who"_ as the subject of a sentence.
CC BY-SA 3.0
2016-03-23T17:23:14.970
33086
2016-03-23T17:23:14.970
5229
33078
answer