Grammatically Correct: The writer's essential guide to punctuation ...

GRAMMAR
WHEN DO YOU USE WHO AND WHEN WHOM?
Use who and whoever when the pronoun should be in the subjective
case; use whom and whomever when it should be in the objective
case.
Exercise
1. (Who/Whom) shall I say is calling?
2. To (who/whom) do you wish to speak?
3. She was the one (who/whom) we wanted to support.
4. I was hoping to meet this mystery man, (who/whom) she said is her
masseur.
5. (Who/Whom) do you think will win?
6. (Who/Whom) do you think they'll choose?
7. We asked only those employees (who/whom) we figured would be
interested.
8. We asked only those employees (who/whom) we figured the
customers would believe.
Answers
1. who
2. whom
3. whom
4. who
5. who
6. whom
7. who
8. whom
In sentences 1, 4, 5 and 7, the pronoun is associated with an
action or a description (calling, being a masseur, winning, being
interested), and hence takes the subjective case. In sentences 2, 3,
6 and 8, the pronoun is the target of someone else's action (being
spoken to, being supported, being chosen, being believed), and
hence takes the objective case.
A helpful trick is to mentally recast the phrase so that it would
take either him or he, which are more intuitively understood. If it
would take him, go with whom (both of which end in m); if it would
take he, go with who (neither of which ends in m). (This mnemonic
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