pronoun case

Pronoun case is the form a pronoun takes according to the work it does in the sentence. The subject case — I, you, he, she, it, we, they, who — is for the doer; the object case — me, you, him, her, it, us, them, whom — is for the receiver of the action or the object of a preposition; the possessive — my, your, his, her, its, our, their, whose — marks ownership and never takes an apostrophe. Most mistakes come from two places. A pronoun after than or as keeps the case the comparison implies: she is faster than I means than I am, while than me means than me as an object. And a compound structure such as between you and I feels formal but is wrong, because between is a preposition and takes the object form, so it is between you and me. Strip the sentence to the pronoun alone and the form usually announces itself.