Understanding Who and Whom
Use who as the subject of a sentence, and whom as the object. To help you remember, try substituting "he" or "him." Use "who" where you would use "he," and use "whom" where you would use "him."
- Who wants ice cream? He wants ice cream.
- Whom is this ice cream for? This ice cream is for him.
- He phoned him. Who phoned whom?