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Possessives and Attributives
Q. I think there’s a contradiction in your examples of the correct use of apostrophes. CMOS 7.20 states that in the case of a place-name ending with “s,” the “s’s” formation is not used; e.g., the United States’. However, 7.17 uses Kansas’s as an example of proper usage. Is that correct?
A. Kansas’s is indeed correct. The tricky part of paragraph 7.20 says to omit the extra s from place-names ending in s “with a plural form,” and Kansas doesn’t qualify as a plural form, even though it happens to end in s (singular Kansas; plural Kansases; there is no singular Kansa). The form of States, in contrast, is plural (singular state; plural states), even though the proper noun United States is singular. Plural forms ending in s take an apostrophe without a second s, whether the word is singular or plural: the United States’ reputation. But singular forms like Kansas take that second s, and thus it’s Kansas’s.