Apostrophes (’) are used for three reasons: possession (boy’s bike), contraction (don’t) or omission (Rock ’n’ Roll). Today I’ll cover possession.

If the owner is singular, add the apostrophe before the s. The boy’s book.

If the owner is plural, add the apostrophe after the s. The girls’ sleepover.

If the owner is plural without an s, add ’s. The women’s room.

It the owner is it, do not add an apostrophe. The court said its decision was fair.

Do not add an apostrophe on plural words that are not possessive. The dogs barked.