Overview
Apostrophes have two main uses in English: to show possession (the teacher's book, the students' work) and to mark missing letters in contractions (don't = do not, it's = it is). A common error is confusing its (possessive) with it's (it is).
Two Uses
- ContractionReplacing omitted letters: don't, it's, I've, they're
- PossessiveShowing ownership: Tom's car, the team's result
- Plural pos.Plural nouns ending -s: the students' books
- IrregularIrregular plural: children's, women's, men's
Critical Distinctions
- it's = it is / it has · its = possessive (no apostrophe)
- they're = they are · their = possessive · there = place
- you're = you are · your = possessive
- NEVER use apostrophe for plural: ❌ apple's → ✅ apples
Common Mistakes
- ❌ The dog wagged it's tail → ✅ its tail (possessive)
- ❌ The student's are ready → ✅ The students are ready (plural, no possession)
- ❌ Chris' car (BrE accepts this) → ✅ Chris's car (most style guides)
When to use
Contractions
I can't believe she didn't call.
Singular pos.
This is my sister's flat.
Plural pos.
The students' projects were excellent.
its vs it's
The cat licked its paw. / It's raining.