mine

Can you lend me a pen? I can’t find the mine.
Can you lend me a pen? I can’t find mine.

Mine is a possessive pronoun. Do not use the before it, and do not put a noun after it: ‘This pen is mine.’

Use the possessive adjective my before a noun: ‘This is my pen.’

Compare: ‘This is my pen.’ ‘This pen is mine.’

Check our grammar lesson on possessive pronouns and possessive adjectives.