1. I don't know who I should hire.

2. I don't know who to fire.
3. I don't know whom I should hire.
4. i don't know whom to hire.
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Which ones are grammatical?
English - Writeacher, Tuesday, May 27, 2014 at 7:19am
Only 3 and 4 are correct.
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Thank you for your help.
I needed to correct one sentence....

1. I don't know who I should hire.
2. I don't know who to hire.

(Is #2 grammatical?)

Neither is correct because the relative pronoun needs to be in the object case, not the subject case.

I don't know whom I should hire.
(because you'd also say, "I should hire him.")

I don't know whom to hire.
(because you'd also say, "I want to hire him.")

Hello

did you get the solution

Yes, sentence #2, "I don't know who to hire," is grammatically correct. In this sentence, the pronoun "who" is used as the object of the verb "to hire." Since it is the object of the verb, the objective form "who" is used instead of the subjective form "whom."