If you’re like most English speakers, you know that there’s a difference between who and whom but you aren’t sure what that difference is.
We’re here to help. Who should be used to refer to the subject of a sentence. Whom should be used to refer to the object of a sentence.
When in doubt, try this simple trick: If you can replace the word with ‘he’ or ‘she,’ use who. If you can replace it with ‘him’ or ‘her,’ use whom.
Here are two examples: Who ate my sandwich? (Did he eat my sandwich? Did she eat my sandwich?)
Whom should I talk to about labeling food in the refrigerator? (Should I talk to him? Should I talk to her?) More here: