As for possessive pronouns like “its,” “whose” and “hers,” all you can do is remember that possession is incorporated into the word, so there’s no need for an apostrophe.

Possessive pronouns. In school, we heard over and over that a possessive takes an apostrophe. But the lesson about possessive pronouns doesn’t seem to get as much play.

The pronoun agreement comes into play when you add a possessive element to these sentences. "She types on her computer," and "they type on their computers." 12.

This is because possessive pronouns don't have apostrophes, even the ones with an s. Properly, it's his, hers, yours, theirs, whose, though many people get those wrong.