It: It was him who she had mentioned before she died

English as a Second Language English Vocabulary, Grammar and Idioms
1

Dear teachers,

Please choose the correct sentences:

  1. It was him who she had mentioned before she died.
  2. It was him that she had mentioned before she died.
    3.It was him she had mentioned before she died.

Is there a rule?
I think all are correct. How about you?
Quoc

2

Hi,

I have a question for you. Where did you find these sentences?

Alan

3

All are correct in grammar?

These are from my teacher.