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What is an apostrophe?

An apostrophe is a punctuation mark used to show possession, to indicate the plural form of letters of the alphabet, and to form a contraction.

How should apostrophes be used?

  • Use an apostrophe and -s (-’s) to show possession of singular nouns.
    • the author’s main point
  • Use an apostrophe and -s (-’s) to show possession of indefinite pronouns.
    • someone’s books
  • Use an apostrophe and -s (-’s) to show possession of irregular plural nouns.
    • the women’s scarves
  • Use an -s followed by an apostrophe (-s’) to show possession of plural nouns.
    • the students’ final grades
  • Use an apostrophe and -s (-’s) to form the plural of letters of the alphabet.
    • Watch your p’s and q’s.
  • Use an apostrophe to form a contraction.
    • The contraction of do not is don’t.

Avoid misuse of apostrophes

  • Do not use an apostrophe in possessive pronouns.
    • Incorrect: That notebook is your’s, and those pens are their’s.
  • Do not use an apostrophe in plural nouns that are not possessive.
    • Incorrect: Please ask the instructor’s to make an announcement to their student’s.
  • Do not use an apostrophe in the word its unless it’s the contraction for it is.
    • Incorrect: The lost dog has a sad look on it’s face.

 For additional information on Apostrophes, see also: