What is the Difference Between a Possessive Pronoun and a Possessive Adjective

The difference between a possessive pronoun and a possessive adjective is best understood when the definitions of each are clear. A pronoun is a term used in place of a noun: she, you, they, we, and it. An adjective is used to modify or describe a noun, or in some cases an adverb: Ugly dog, beautiful tree, tasty soup.
People may get confused with the distinctions between a possessive pronoun and a possessive adjective because the words used as possessive pronouns are often slight modifications of the words used for possessive adjectives. The main distinction is that the possessive pronoun is used in place of a noun, while the possessive adjective will always modify a noun.

Consider the following example:
The car is Sally’s.
If we want to substitute in a possessive pronoun to replace the noun Sally’s, we’d merely write:
The car is hers.
This is clearly a possessive pronoun since we have taken out the possessive noun Sally’s and replaced it with hers.
When you’re trying to determine the difference between a possessive pronoun and a possessive adjective, a further example helps. If we want to use a possessive adjective, we might write:
That is her car.
Suddenly, instead of using a pronoun, we have used her to modify and further describe the noun car, Her is an adjective in this case, indicating possession.
It can help you understand differences between a possessive pronoun and a possessive adjective when you see a list of those most commonly used. Simple possessive pronouns include: mine, his, hers, ours, theirs, your. Simple possessive adjectives include: my, his, her, your, our, their. The terms its and his can stand either as possessive pronouns or possessive adjectives, but most words undergo a slight change. In general, with the exception of his, its, my, mine most possessive adjectives end in an s.
For extra practice, indicate in the next ten sentences whether the italicized words are possessive pronouns or possessive adjectives. (Answers are below, but don’t cheat!)
1. My mother went to the store.
2. I can’t find her keys.
3. I think that dog is yours.
4. The cat chased its tail.
5. That opinion is theirs not ours.
6. Can you help our sister move?
7. That coat is definitely his.
8. Your haircut looks great.
9. I believe yours is in the back.
10. That cookie is mine.

Answers: 1,2,4,6,8 are possessive adjectives. 3,5,7,9,10 are possessive pronouns.
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