Apostrophes
An apostrophe (’) is a punctuation mark that either shows ownership (Susan’s) or indicates that a letter has been intentionally left out to form a contraction (I’m, that’s, they’re).
APOSTROPHES TO SHOW OWNERSHIP
Add -’s to a singular noun to show ownership even if the noun already ends in -s.
Karen’s apartment is on the South Side.
If a noun is plural and ends in -s, just add an apostrophe. If it is plural but does not end in -s, add -’s.
The twins’ father was building them a playhouse.
[more than one twin]
The children’s toys were broken.
The placement of an apostrophe makes a difference in meaning.
My sister’s six children are at my house for the weekend.
[one sister who has six children]
My sisters’ six children are at my house for the weekend.
[two or more sisters who together have six children]
Do not use an apostrophe to form the plural of a noun.
Do not use an apostrophe with a possessive pronoun. These pronouns already show ownership (possession).
Possessive Pronouns
| my | his | its | their |
| mine | her | our | theirs |
| your | hers | ours | whose |
| yours |
The single most common error with apostrophes and pronouns is confusing its (a possessive pronoun) with it’s (a contraction meaning “it is”). Whenever you write it’s, test correctness by replacing it with it is and reading the sentence aloud to hear if it makes sense.
APOSTROPHES IN CONTRACTIONS
A contraction is formed by joining two words and leaving out one or more of the letters. When writing a contraction, put an apostrophe where the letter or letters have been left out.
She’s on her way. = She is on her way.
I’ll see you there. = I will see you there.
Be sure to put the apostrophe in the correct place.
Common Contractions
| aren’t = are not | I’d = I would, I had |
| can’t = cannot | I’ll = I will |
| couldn’t = could not | I’m = I am |
| didn’t = did not | I’ve = I have |
| don’t = do not | isn’t = is not |
| he’d = he would, he had | it’s = it is, it has |
| he’ll = he will | let’s = let us |
| he’s = he is, he has | she’d = she would, she had |
| she’ll = she will | won’t = will not |
| she’s = she is, she has | wouldn’t = would not |
| there’s = there is | you’ll = you will |
| they’re = they are | you’re = you are |
| who’s = who is, who has | you’ve = you have |
Apostrophes with Letters, Numbers, and Time
Use -’s to make letters and numbers plural. The apostrophe prevents confusion or misreading.
In Scrabble games, there are more e’s than any other letter.
In women’s shoes, size 8’s are more common than size 10’s.
Use an apostrophe or -’s in certain expressions in which time nouns are treated as if they possess something.
She took four weeks’ maternity leave after the baby was born.
This year’s graduating class is huge.