The Apostrophe’s Other Life
That’s no problem with these pronouns: my, mine, your, her, our, and their. It gets muddier with pronouns that end in “s”: his, yours, hers, theirs, and the really tough one its.
Examples:
The desk chair is hers.
The earnings are theirs.
The dog ate its bone.
If the singular thing you are writing about owns something, it’s “its.” Period.
The it with an apostrophe, it’s, has a different meaning all together. It’s means “it is.” The word is a contraction, with the apostrophe filling in for the letter “i” in “is.” Contractions can be made up of the following words:
Pronouns + verbs: I’m, they’re, he’ll, she’s, and the dreaded you’re (not the same as the possessive “your”) and they’re (not the same as the possessive “their” or the directional “there”)
Nouns + verbs: Azalea’s going to the store. That dog’ll hunt.
Verbs + “not”: isn’t, aren’t, and won’t (which is really “will not.”)