Possessive adjectives and pronouns
The short answer
A possessive adjective comes before a noun: my car, their house. A possessive pronoun replaces the whole phrase and stands alone: that car is mine. Neither ever takes an apostrophe, and neither agrees with the thing owned, only with the owner.
The rule
English marks possession in two ways with pronouns. The possessive adjectives (my, your, his, her, its, our, their) modify a noun and cannot stand without one. The possessive pronouns (mine, yours, his, hers, ours, theirs) replace an entire noun phrase and stand alone. Unlike French, Spanish or German, they agree with the owner rather than with the thing owned, so his sister and his brother use the same word. None of them takes an apostrophe.
| Form | Structure | Example |
|---|---|---|
| Possessive adjective | before a noun | my, your, his, her, its, our, their |
| Possessive pronoun | stands alone | mine, yours, his, hers, ours, theirs |
| Agreement | with the ownernever the thing | his sister, his brother |
| Apostrophes | never on possessive pronouns | its, yours, theirs |
| Nouns | apostrophe s for the owner | Anna’s car, the students’ results |
| Of + noun | usual for things | the roof of the building |
Part 1 of 3
Adjective or pronoun
The test is whether a noun follows. My bag needs the noun; the bag is mine does not. Only his is identical in both sets, which is why it never causes trouble and everything else occasionally does.
Possessive pronouns also appear after of in a construction English uses to combine two determiners: a friend of mine, that idea of yours. A my friend is impossible, which is exactly why this construction exists.
Is this your coat? No, mine is the black one.
Adjective, then pronoun.
Their flat is bigger than ours.
Their takes a noun; ours stands alone.
She’s a colleague of mine.
Of plus a possessive pronoun.
Part 2 of 3
Agreement with the owner
English possessives tell you about the owner, not the thing owned. His sister, his brother, his books: all the same word, because the owner is male. French and Spanish do the opposite, agreeing with the noun that follows.
That is why sa sœur and sa voiture translate as his sister and his car if the owner is male, and her sister and her car if she is. French speakers regularly produce his for a female owner and her for a male one, because their own language gives no clue.
Marc showed me his photos of his wife.
His twice, because Marc owns both.
Claire lost her keys and her phone.
Her twice, whatever the objects are.
The team published its findings.
Its for an organisation, no apostrophe.
Part 3 of 3
The apostrophe rules
No possessive pronoun takes an apostrophe: its, yours, hers, ours, theirs. The apostrophe forms (it’s, you’re, who’s, they’re) are all contractions of a verb, and confusing the two is the most frequent written error in English.
Nouns are the opposite: they do take an apostrophe. Singular adds ’s: Anna’s car, and a plural already ending in -s adds only the apostrophe, the students’ results. Irregular plurals take ’s: the children’s books.
The cat licked its paw.
Possessive, so no apostrophe.
It’s been raining all week.
A contraction of it has.
That’s my parents’ house.
Plural owner already ending in -s.
Mistakes to avoid
What learners actually get wrong
The company changed it’s name.
The company changed its name.
It’s always means it is or it has. The possessive its takes no apostrophe, which looks inconsistent next to Anna’s and is nonetheless the rule for every possessive pronoun.
This book is my.
This book is mine.
Standing alone requires the pronoun form. My cannot end a sentence because it needs a noun to attach to.
Marie showed me his new flat.
Marie showed me her new flat.
English possessives agree with the owner. This error comes straight from French and Spanish, where the possessive agrees with the thing owned and so gives no information about who owns it.
A my friend told me.
A friend of mine told me.
English cannot stack two determiners, so a and my cannot both precede the noun. The of construction exists precisely to combine them, and it is the natural fix.
Questions
Asked and answered
- Why is there no apostrophe in its?
- Because possessive pronouns never take one, his, hers, ours, theirs and yours all behave the same way. The apostrophe in it’s marks a missing letter, exactly as in don’t. Nouns are the exception, not the pronouns.
- When do I use ’s and when of?
- ’s for people and animals, Anna’s bag, the dog’s lead, and of for things: the roof of the building. The line is soft, and time expressions take ’s freely: a day’s work, two weeks’ notice.
- Is “their” acceptable for one person?
- Yes. Singular they and their have been standard for centuries when the gender is unknown, someone left their coat, and are now widely accepted for a known person who uses them. Every major style guide permits it.