1. Subject vs. Object
* Whoever is used as the subject of a verb. Think of it as replacing "he/she/they" in a sentence.
* Whomever is used as the object of a verb or preposition. Think of it as replacing "him/her/them" in a sentence.
2. Determining Subject/Object
To determine whether you need "whoever" or "whomever," ask these questions:
* Subject: Who/what is doing the action?
* Object: Who/what is receiving the action or being affected by the preposition?
3. Examples
* Whoever comes to the party is welcome. (Whoever is the subject of the verb "comes")
* Give the prize to whomever wins the contest. (Whomever is the object of the preposition "to")
* I'll vote for whoever I think is the best candidate. (Whoever is the subject of the verb "think")
* The police arrested whomever they found at the scene. (Whomever is the object of the verb "arrested")
4. Common Mistakes
* Avoid using "whomever" as the subject of a verb.
* Avoid using "whoever" as the object of a verb or preposition.
5. Tip
If you're unsure, try substituting "he/she/they" or "him/her/them". If "he/she/they" fits, use "whoever". If "him/her/them" fits, use "whomever".
Examples:
* Correct: I'll vote for whoever I think is the best candidate. (I'll vote for *he/she*.)
* Incorrect: I'll vote for whomever I think is the best candidate. (I'll vote for *him/her*.)