Possessive Pronouns

Possessive pronouns are used in English to avoid repeating information that is already clear.

This book is my book, not your book.(Sounds repetitive)
This book is mine, not yours.(Sounds more native)

In the sentence, mine and yours are possessive pronouns that respectively replace my book and your book.

Subject Possessive Pronouns
IMine
YouYours
HeHis
SheHers
ItIts
WeOurs
YouYours
TheyTheirs

Her car is faster than mine.
(Her car is faster than my car)

I know this drink is yours but I need to drink something.
(I know this drink is your drink but I need to drink something)

I know this drink is yours but I need to drink something.
(I know this drink is your drink but I need to drink something)

I don’t have a car today, so James will bring his.
(James will bring his car)

I didn’t have my umbrella so Marta lent me hers.
(I didn’t have my umbrella so Marta lent me her umbrella)

That food is ours and not theirs.
(That food is our food and not their food)

Our house a bit cramped, but theirs is so spacious.
(Their house is so spacious)