Student or Learner
I'd like to ask if it is OK to say 'talk to who' informally instead of using 'whom' as in:
A: You need to talk to someone.
B: Talk to who?
Is the usage of 'who' is OK in an informal conversation?
Is it grammatically correct? No.
Will you frequently hear it even though it's incorrect? Yes.
The who/whom distinction is rarely used correctly even by native speakers, and the distinction seems to be dropping out of usage altogether.
That being said, I guess it's your decision on whether you wish to break the grammar rules. I will say it's not one of those errors anyone is likely to notice, nor will it cause any confusion or misunderstanding.
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