Tutorial for Apostrophe Usage

What is it?

Use apostrophes for three purposes: to show possession, to indicate an omission, and to add an ending to a number, letter, or abbreviation.

1. To make a singular noun possessive, add ’-s.

   The surgeon's excellent reputation calmed Larissa’s fears.

2. To make a plural noun ending in -s possessive, add an apostrophe.

   The researchers’ instruments were not properly sanitized.

3. To make a plural noun not ending in -s possessive, add -’s.

   The temple offers a divorced women’s support group.

4. Use an apostrophe to indicate an omission in a contraction.

   I can’t meet you at the gym; I’ve got too much homework tonight.

5. Use an apostrophe to form the plural of an abbreviation and of a letter, word, or number mentioned as a word.

   My aunt is a member of the ACLU’s advisory board.

How to correct errors

1. Apostrophes are used to make singular nouns possessive.

   The lawyer’s office needed a complete renovation.

2. Apostrophes are used to make a plural noun ending in -s possessive.

   Students’ complaints can be brought to the attention of the dean.

3. Add an ’-s to make a plural noun not ending in -s possessive.

   The children’s day care center shut down after months of mismanagement.

4. Apostrophes indicate an omission in a contraction.

   You didn’t have to return the dress-I would’ve worn it.

5. Apostrophes form the plural of an abbreviation and of a letter, word, or number mentioned as a word.

   FDR’s New Deal program is arguably his greatest legacy.