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Possessives and Attributives
Q. The following sentences were written by a student. “The three of us went to the Rangers’ hockey game. The leprechaun is the Celtics’ mascot.” Are apostrophes needed or do the sentences contain attributive nouns?
A. In these cases, the attributive might be more conventional, but the possessive is not wrong, and I would hate to discourage a student’s correct use of apostrophes. I’d give her a gold star, along with an explanation of the alternative styling as attributives. (For a more detailed explanation and examples, see CMOS 7.27.)