Is this sentence grammatically correct: "One of the hardest questions on the subject is who gets to decide whom is an Outsider."Is the "whom" correct? Should the sentence end in a question mark?
This sentence is a statement and does not need a question mark. However the use of "whom" in this case is incorrect. Whom is only used as an object. Here is how to test when you use "who" or "whom" in a sentence. Replace "who" or "whom" with the pronoun "he" or "him". If "he" fits, then use who. If "him" fits, then use whom.
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