例えば"This is my book"です。一方所有代名詞は名詞の代わりに使います。
例えば、"This is my pen and that is her pen",と言う代わりに、私達は"This is my pen and that is hers"と言います。
What's the difference between a possessive adjective and a possessive pronoun? The difference between a possessive adjective and a possessive pronoun is that we put a possessive adjective in front of a noun whereas we use a possessive pronoun instead of a noun.
Is this ear yours? No that ear isn't mine. It's yours.
Is that suit hers? No, that suit isn't hers; it's his.
Are these books theirs? No, these books aren't theirs; they're ours.