Who vs Whom

—>Who and whom are both pronouns (words that can be used as a noun or noun phrase) meaning ‘what or which person or people.’

—>Who is used when referring to the subject of a sentence (the person, place, or thing performing the action/verb of the sentence).
Examples: Who is the richest person alive? Who will win?
Clarification: ‘Who’ is performing the action (is; will win) in these sentences, meaning ‘who’ is the subject.

—>Who is also used when referring to the subject of a dependent clause (a phrase that provides additional information, but that cannot stand alone as a sentence) regardless of if that clause refers to the subject or object of the entire sentence.
Example: I was talking to the man who didn’t want to leave.
Clarification: ‘who didn’t want to leave’ is a dependent clause. In this sentence, this clause adds information about the object (man), but within the clause itself, ‘who’ is performing the action/verb (did {not} want) which makes ‘who’ the subject of the clause. So ‘who’ is used instead of ‘whom.’
Example: The boy who stormed the gate was injured.
Clarification: ‘who stormed the gate’ is a dependent clause. In this sentence, this clause adds information about the subject (boy), but within the clause itself, ‘who’ is performing the action/verb (stormed) which makes ‘who’ the subject of the clause. So ‘who’ is used instead of ‘whom.’

—>Whom is used when referring to the object of a sentence (the person, place, or thing receiving the action/verb of the sentence).
Example: Whom do you think will win?
–Clarification: ‘You’ is the subject and ‘do think’ is the verb. ‘Whom’ is the object. The sentence is asking ‘You (do) think whom will win?’ not ‘Whom do think you will win?’
Example: I don’t know whom to pick.
-Clarification: ‘I’ is the subject and ‘do (not) know’ is the verb. ‘Whom’ is the object. The sentence is saying ‘I do not know,’ not ‘whom do not know.’
Example: To whom is the letter addressed?
-Clarification: ‘Letter’ is the subject and ‘is addressed’ is the verb. ‘Whom’ is the object. The sentence is asking ‘The letter is addressed to whom?’ not ‘Whom is addressed to the letter?’

—>If you’re still unsure, replace who/whom with she or he. If it still makes sense, then use who.
Example: Who/whom is the richest person alive? He/she is the richest person alive? (MAKES SENSE, USE WHO)
Example: Who/whom will win? He/she will win? (MAKES SENSE, USE WHO)
Example: Who/whom do you think will win? He/she do you think will win? (DOES NOT MAKE SENSE, USE WHOM)
Example: To who/whom is the letter addressed? To he/she is the letter addressed? (DOES NOT MAKE SENSE, USE WHOM)

—>When it comes to dependent clauses, drop everything but who/whom and the verb of the clause before replacing who/whom with he/she.
Example: The boy who/whom stormed the gate was injured. He/she stormed the gate. (MAKES SENSE, USE WHO)
Example: I was talking to the man who/whom didn’t want to leave. He/she didn’t want to leave. (MAKES SENSE, USE WHO)