‘Whom’ is a pronoun that is used to refer to the object of a verb or preposition. It is used when referring to a person who is receiving an action. In other words, ‘whom’ is used when asking about the person receiving the action. Examples: To whom did you give the book? Whom did you see at the party last night? From whom did you receive the email?
Who refers to someone performing the action of a verb (e.g. "They are the ones who sent me the gift"), and whom refers to someone receiving the action of a verb ("I'd like to thank the gift-givers, whom I've known for years"). In grammar terms, that makes who a subject, and whom an object.
Who is the subject of a sentence or clause (who is performing the action), whereas whom is the object of a verb or preposition (whom is affected by the action).
Use this they/them method to decide whether who or whom is correct.
If who/whom is an object (the one receiving the action), use whom. Let’s look at our first example: Think about who you want to cover and who is eligible for coverage.
Who or Whom? Get It Right Every Time with These 3 Tricks
Language evolves over time, and “whom” is quite rare in modern usage. If you say “Who should I talk to?” instead of “Whom should I talk to?”—most people won’t notice.
Who vs Whom: 4 Easy Ways to Get It Right Every Time
Do you know how to use "who" and "whom" correctly in a sentence? Learn how to determine their use in this article.