The Editor’s Manual
Free learning resource on English grammar, punctuation, usage, and style.
Form the possessive of a plural name by placing an apostrophe after the “s” that makes the plural, as you would for any other plural noun.
“You’re” is the contraction of “you are,” while “your” is the possessive form of “you.” Don’t use “your” to mean “you are.”
Use an apostrophe after “s” in “Teachers’ Day.” The noun “teachers” is thought of as a plural possessive, indicated by an apostrophe after “s.”
“Indigenous Peoples’ Day” may be written with or without the apostrophe, depending on the style you follow.
There is no apostrophe in “Veterans Day.” The noun veterans is considered descriptive instead of possessive in the name of this holiday.
Both styles are correct: “Presidents’ Day” (possessive, with the apostrophe) and “Presidents Day” (descriptive, without the apostrophe).
Place an apostrophe before “s” in Mother’s Day and Father’s Day. Also capitalize the two words that make up the name of the holiday.
Use an apostrophe with possessive nouns (New Year’s Day, Mother’s Day, Presidents’ Day) but not with descriptive terms (Christmas Eve, Human Rights Day).
“It’s” (with the apostrophe) is a contraction of “it is” or “it has.” “Its” (without the apostrophe) is the possessive form of “it.”
“Who’s” is the contraction of “who is” or “who has,” while “whose” is the possessive form of “who.”