Who vs. Whom: Grammar Rules and Examples

Grammar Rules for Who and Whom

Use who when the pronoun is the subject of its clause. Whom is the formal object form, although object who is standard in ordinary modern English when no preposition comes directly before it^[1][2][3][3].

When to Use Who

Use who when the pronoun is the subject of the clause or sentence, meaning it is performing the action described by the verb. This is analogous to using subject pronouns like he, she, or they. Examples include the sentences:

• “Who would like to be on your team?”
• “Who made those beautiful hats?”

In these examples, “who” is performing the action of wanting and making, respectively^[1][2][4].

When to Use Whom

Use whom when the pronoun is the object of a verb or a preposition, meaning it receives the action or completes the meaning of a preposition. This corresponds with object pronouns such as him, her, or them. Examples are:

• “To whom was the letter addressed?”
• “Whom do you believe?”
• “I do not know with whom I will go to the concert.”

Here, “whom” is the object of the preposition or the verb’s action^[1][2][3].

The He/She vs. Him/Her Substitution Trick

A widely recommended method to determine the correct usage of who or whom is the substitution test. If replacing the pronoun with he or she fits grammatically, use who. Conversely, if him or her fits, use whom. For example:

• “Who called me?” → “He called me.” → correct use of who
• “Whom did you call?” → “You called him.” → correct use of whom

This method works because he/she are subject pronouns, just like who, and him/her are object pronouns, like whom^[1][2][4][5].

Verb and Subject Identification Trick

Another approach involves analyzing the verbs in the sentence and identifying their corresponding subjects:

1. Find all the verbs.
2. Identify the subject performing each verb.
3. If who/whom is the subject performing the action, use who.
4. If who/whom is the object receiving the action, use whom.

This strategy reinforces the subject-object distinction that separates these pronouns^[1].

Usage After Prepositions and in Relative Clauses

Whom is preferred after prepositions such as to, with, for, by, and from. For example:

• “To whom should I address this letter?”
• “With whom are you going?”

In formal writing, using with whom is standard and grammatically correct. When the preposition is stranded at the end, object who is standard in ordinary English, as in “Who are you going with?” The fronted form “With whom are you going?” is more formal^[2][3][3].

Also, whom can be used as a relative pronoun to connect a relative clause to the main clause, especially in formal contexts. Whether the relative clause is essential or nonessential influences punctuation with commas^[2].

Examples of Correct Usage in Sentences

• Who is inviting everyone to the party? (subject performing the inviting)
• She knows who will be attending the meeting. (subject of the verb “will be attending”)
• Whom did you see at the concert? (object receiving the action “did see”)
• This is the person to whom I gave the book. (object of the preposition “to”)
• I’m not sure whom they hired for the job. (object of the verb “hired”)
• The candidate whom the committee selected impressed everyone. (object in relative clause)

These sentences illustrate the correct grammatical usage according to the role the pronoun plays^[1][2][3].

Informal Usage Notes

While whom is grammatically precise for object positions, it often sounds fussy or unnatural in everyday conversation. In many casual contexts, speakers use who in place of whom without causing confusion or misunderstanding. However, in formal writing and professional communication, maintaining the who/whom distinction is considered proper^[3].

Below are a few practice sentences designed to test the understanding of who vs. whom usage. Try to decide which pronoun fits best, then apply the substitution trick or verb-subject identification:

1. ___ is coming to dinner tonight?
2. For ___ did you buy this gift?
3. ___ told you about the meeting?
4. To ___ should I send the invitation?
5. With ___ are you going to the movies?

Answer key:

1. Who (He/She is coming)
2. Whom (For him/her did you buy)
3. Who (He/She told you)
4. Whom (To him/her should I send)
5. Whom (You are going with him/her; the fronted preposition requires the formal object form)

Advanced Examples and Edge Cases

Sometimes, deciding between who and whom can be tricky, especially in complex sentences with embedded clauses or when the pronoun switches function. Consider these nuanced examples:

• “Who do you think will win the race?” Here, who is the subject of the verb “will win,” despite “do you think” preceding it.
• “Whom do you think they will choose?” In this case, even though the sentence is complex, whom remains the object of “will choose.”
• “To whom it may concern” uses whom as the object in a fixed formal salutation and places it after the fronted preposition to.

Practical Step-by-Step Method

To systematically determine whether to use who or whom, try the following:

1. Isolate the clause that contains the pronoun. Simplify the sentence to its core clause.
2. Identify the verb and ask who or whom is acting or being acted upon.
3. Apply the substitution test: replace the pronoun with “he” or “him.” If “he” fits, the pronoun is who; if “him” fits, then it is whom.
4. Check for prepositions preceding the pronoun. Prepositions generally require whom.

By applying this step-by-step method, even deeply nested sentences become manageable.

Comparing Who and That

Who typically refers to people. It is required as a subject in direct questions and is also standard as an object in ordinary English. Whom is the formal object form.

In a restrictive relative clause, that can refer to a person as either subject or object: “The woman that called you is here” is grammatical, though many editors prefer who for people. That is not used in a nonrestrictive clause or directly after a fronted preposition; write “My mentor, who called yesterday” and “the person to whom I wrote.”

Common Mistakes and How to Avoid Them

• Using whom as the subject where who is correct: “Whom is at the door?” (incorrect; should be “Who is at the door?”)
• Treating object who as an error in “Who did you go with?” That sentence uses standard object who with a stranded preposition; “With whom did you go?” is the formal alternative.
• Overcorrecting and using whom unnecessarily where who is correct: “Whom wants to join?” (incorrect)

Avoid these errors by always applying subject-object logic and substitution tests before choosing.

Practice with Relative Clauses

Try these relative clause sentences to solidify your understanding:

• “The student who answered the question correctly won a prize.” (who as subject of “answered”)
• “The teacher to whom the letter was addressed is absent.” (whom as object of “to”)
• “She is someone whom everyone admires.” (whom as object of “admires”)

Summary Table for Quick Reference

Function	Correct Pronoun	Example Sentence
Subject of verb	Who	Who is calling?
Object of verb	Whom	Whom did you call?
Object of preposition	Whom	To whom did you speak?
Subject in embedded clause	Who	I know who is coming to dinner.
Object in embedded clause	Whom	She is the one whom I trust.