Choosing between the subjective case and objective case is sometimes complicated by appositives, and the as or than construction. The confusion over the choice of who or whom is a good example of this problem.
Pronoun case with appositives
An appositive is a word or group of words that restates or identifies the noun or pronoun it is next to: My sister Heather; John, the gardener; our friend Carlos; We, the people. The presence of an appositive doesn't change the rule for pronoun case; that is, use the subjective case for subjects and the objective case for objects.
- The decision to close the pool was a setback for us swimmers. ( not for we swimmers)
The best way to make sure you have chosen the correct pronoun case is to read the sentence without the appositive: The decision to close the pool was a setback for we. You can see that us is the right pronoun to use.
Choosing the right pronoun case after as or than can be difficult.
You admire Professor Morrow more than I.
You admire Professor Morrow more than me.
Depending on the meaning, either choice could be correct. If the writer means You admire Professor Morrow more than I (admire Professor Morrow), then the first sentence is correct. If the writer means You admire Professor Morrow more than (you admire) me, then the second sentence is correct.
The key to choosing the right pronoun case is to mentally supply the missing part of the clause.
Did you work as hard as they? ( worked)
I like Ed better than he. ( likes Ed)
I like Ed better than him. ( than I like him)
They are smarter than we. ( are)
If a sentence sounds awkward to you—for example, They are smarter than we—you can avoid the problem by supplying the missing word: They are smarter than we are.
Who, whom, whoever, whomever
These pronouns cause so much confusion that they are being treated separately, even though the rules about case are the same as those for I, he, she, we, and they.
As a subject, choose who or whoever. Who/whoever must be followed by a verb because it is the subject.
She was the player who won the game. ( who is the subject of won)
Whoever wants the paper can have it. ( Whoever is the subject of wants)
As an object, choose whom or whomever. Whom/whomever is not followed by a verb because it is an object.
- He was a person around whom controversy swirled. ( whom is the object of the preposition around)
Whomever will you invite? ( You will invite whomever: direct object of invite). In casual conversation and informal writing, whom is used infrequently. At the beginning of questions, for example, who is often substituted for whom, even when whom is grammatically correct, as in the following informal sentences.
- Who will you marry? (You will marry whom.)
- Who did he ask? (He did ask whom.)
Maybe whom will disappear from the language someday. Does this mean you should ignore it? No, it is still best to correctly distinguish between who and whom.