This topic confuses a lot of people…almost everyone that I’ve talked to, but it doesn’t need to be so difficult. This is one of the rules of grammar that I never truly understood until I tool a Precision Language course in college. When I finally understood the concept, I couldn’t believe that I hadn’t understood it sooner! I’ll try to make this easy, so that you will never ask yourself again, “Is it who or whom?”
Both words (who and whom) are pronouns (leave a comment if I should explain the parts of a sentence, such as pronouns). The difference lies in their functions.
WHO – subjective pronoun (fancy way to say subject)
WHOM – objective pronoun (the objective of something else, such as a preposition)
WHO ate all the ice cream?
(WHO is the subject of the sentence)
To WHOM should I give the bill?
(WHOM is the object of the preposition ‘to’)
The who/whom dilemma is the same as the difference between he/him and she/her. Let me show you:
HE told me that SHE ate all the ice cream.
(HE and SHE are both the subject of a verb)
I saw HIM last night, and he said to send the bill to HER.
(HIM is the direct object of the verb; HER is the object of the preposition.
I hope that helps!