The rules of when to use who/whoever and whom/whomever are simple, but sadly, many writers and students struggle with these tricky little pronouns. In casual speech, we almost never use “whom” and “whomever,” so we don't pick it up quite as easily as we do other grammatical rules.
So when do you use “who” or “whoever”? “Who” is the subjective form, meaning that the person to whom it is referring is the subject of the sentence.
Example: Betsy went to the store to buy milk.
Who went to the store to buy milk?
In this example, Betsy is the subject of the sentence, meaning she is the one doing the action. Therefore, when we substitute a pronoun for “Betsy”, that pronoun will be “Who”.
On the other hand, “whom” and “whomever” are the objective form, or the object of the sentence.
Example: Timmy asked Lola to the dance.
Timmy asked whom to the dance? Or, Whom did Timmy ask to the dance?
In this example, Lola is the object of the sentence, meaning that she is the one receiving the action, in this case Timmy's request to go to the dance. Therefore, “whom” is substituted for “Lola”.
Tell the difference with this one weird trick!
Here is a simple and fairly accurate trick you can use to determine which to use: substitute the pronouns “he” and “him” or “she” and “her” to determine when to use “who” and “whom”, and the pronouns “they” and “them” for “whoever” and “whoever”.
Example: Who/Whom eats lunch at the cafe?
Substitute “He” if you want to try “Who” and “Him” if you want to try “Whom”—it's easy to remember the pairs, since “him” and “whom” both end in m. Obviously, in this example, we would say “He eats lunch at the cafe,” not “Him eats lunch at the cafe.” Since “He” works, we would use “Who”.
Example: Timmy kissed the girl whom he liked in first grade.
Here, we would substitute “her”—“Timmy kissed her,” not “Timmy kissed she.” Therefore, “whom” is the correct word to use here.
This has just been a short and simple explanation of the rules of “who” and “whom”. It can be very tricky to figure out which to use sometimes, but I hope this has been a helpful summary of the basics.
