Pronouns often take the place of nouns or other words functioning as nouns so that you do not have to repeat words that have already been mentioned. A word or word group that a pronoun replaces or refers to is called the antecedent of the pronoun.
Pronouns fall into several categories.
Personal pronouns
Personal pronouns refer to specific persons or things. Each can take several forms (I, me, my, mine) depending on its function in the sentence.
I, me, you, he, she, him, her, it, we, they, them
When Keisha saw the dogs again, she called them, and they ran to her.
Possessive pronouns
Possessive pronouns are personal pronouns that indicate ownership. (Apostrophes are not used with possessive pronouns.)
my, mine, your, yours, her, hers, his, its, our, ours, their, theirs
My roommate lost her keys.
Reflexive pronouns
Reflexive pronouns refer to the subject of the sentence or clause in which they appear. They end in -self or -selves.
myself, yourself, himself, herself, itself, oneself, ourselves, yourselves, themselves
The seals sunned themselves on the warm rocks.
Intensive pronouns
Intensive pronouns have the same form as reflexive pronouns. They emphasize a noun or another pronoun.
He decided to paint the apartment himself.
Indefinite pronouns
Indefinite pronouns do not refer to specific nouns, although they may refer to identifiable persons or things. The following is a partial list. For a complete list, see this page. (Other pronouns should not be used in an indefinite sense in formal academic writing.)
all, another, any, anybody, anyone, anything, both, each, either, everybody, everyone, everything, few, many, most, much, neither, nobody, none, no one, nothing, one, some, somebody, something
Everybody screamed, and someone fainted, when the lights went out.
Demonstrative pronouns
Demonstrative pronouns identify or point to specific nouns.
this, that, these, those
These are Peter’s books.
Interrogative pronouns
Interrogative pronouns are used to ask questions.
who, which, what
Who can help set up the chairs for the meeting?
Relative pronouns
Relative pronouns introduce dependent clauses and relate the dependent clause to the rest of the sentence (see clauses). The interrogative pronoun who and the relative pronouns who and whoever have different forms depending on how they are used in a sentence.
who, which, that, what, whoever, whichever, whatever
Maya, who hires interns, is the manager whom you should contact.
Reciprocal pronouns
Reciprocal pronouns refer to individual parts of a plural antecedent.
each other, one another
The business failed because the partners distrusted each other.