I thought that 誰 meant 'who', such as in:

> 彼は誰ですか。'Who is he?'

Then, why in this sentence it is 誰か ('someone') which is used and not 誰?

> 彼女が誰か知っていますか。'Do you know who she is ?'
CC BY-SA 4.0
2021-08-30T11:42:57.230
89117
2021-08-30T19:21:32.820
2021-08-30T19:21:32.820
30454
41663
question
pronouns
Why 誰か and not 誰?
In this context, you can think of `誰か` as a contraction of `誰なのか` which stands
for `who it is`.
CC BY-SA 4.0
2021-08-30T14:08:27.787
89119
2021-08-30T14:08:27.787
32857
89117
answer