What's a pronoun?

A pronoun takes the place of a noun.

There are several types of pronouns -

• A subjective pronoun acts as the subject of a sentence—it performs the action of the verb. The subjective pronouns are he, I, it, she, they, we, and you.               

                                                          

• An objective pronoun acts as the object of a sentence—it receives the action of the verb. The objective pronouns are her, him, it, me, them, us, and you.

• A possessive pronoun tells you who owns something. The possessive pronouns are hers, his, its, mine, ours, theirs, and yours.

Try the quiz on softschools.com for extra credit
http://www.softschools.com/quizzes/grammar/pronoun/quiz227.html