In linguistics and grammar, a pronoun is a pro-form that substitutes for a noun phrase (including a noun phrase consisting of a single noun) with or without a determiner, such as you and they in English. The replaced phrase is the antecedent of the pronoun. A pronoun used for the item questioned in a question is called an interrogative pronoun, such as who.

For example, consider the sentence "John gave the coat to Alice." All three nouns in the sentence can be replaced by pronouns: "He gave it to her." If the coat, John, and Alice have been previously mentioned, the listener can deduce what the pronouns he, it and her refer to and therefore understand the meaning of the sentence. However, if the sentence, "He gave it to her," is the first presentation of the idea, none of the pronouns have antecedents, also called unprecursed pronouns, and each pronoun is therefore ambiguous.

Types of pronouns

Common types of pronouns found in the world's languages are as follows.

• Personal pronouns stand in place of the names of people or things:
• Subjective pronouns are used when the person or thing is the subject of the sentence or clause. English example: I like to eat chips but she does not.
• Second person formal and informal pronouns (T-V distinction). For example, vous and tu in French. There is no distinction in modern English, though Elizabethan English marked the distinction with "thou" (singular informal) and "you" (plural or singular formal).
• Inclusive and exclusive "we" pronouns indicate whether or not the audience is included. There is no distinction in English.
• Intensive pronouns re-emphasize a noun or pronoun that has already been mentioned. English uses the same forms as for the reflexive pronouns; for example: I did it myself (contrast reflexive use I did it to myself).
• Objective pronouns are used when the person or thing is the object of the sentence or clause. English example: John likes me but not her.
• Direct and indirect object pronouns. English uses the same forms for both; for example: Mary loves him (direct object); Mary sent him a letter (indirect object).
• Reflexive pronouns are used when a person or thing acts on itself. English example: John cut himself.
• Reciprocal pronouns refer to a reciprocal relationship. English example: They do not like each other.
• Prepositional pronouns come after a preposition. No distinct forms exist in English; for example: Mary looked at him.
• Disjunctive pronouns are used in isolation, or in certain other special grammatical contexts. No distinct forms exist in English; for example: Who does this belong to? Me.
• Dummy pronouns are used when grammatical rules require a noun (or pronoun), but none is semantically required. English example: It is raining.
• Weak pronouns.
• Possessive pronouns are used to indicate possession or ownership.
• In strict sense, the possessive pronouns are only those that act syntactically as nouns. English example: Those clothes are mine.
• Often, though, the term "possessive pronoun" is also applied to the so-called possessive adjectives (or possessive determiners). For example, in English: I lost my wallet. They are not strictly speaking pronouns because they do not substitute for a noun or noun phrase, and as such, some grammarians classify these terms in a separate lexical category called determiners (they have a syntactic role close to that of adjectives, always qualifying a noun).
• Demonstrative pronouns distinguish the particular objects or people that are referred to from other possible candidates. English example: I'll take these.
• Indefinite pronouns refer to general categories of people or things. English example: Anyone can do that.
• Distributive pronouns are used to refer to members of a group separately, rather than collectively. English example: To each his own.
• Negative pronouns indicate the non-existence of people or things. English example: Nobody thinks that.
• Relative pronouns refer back to people or things previously mentioned. English example: People who smoke should quit now.
• Indefinite relative pronouns have some of the properties of both relative pronouns and indefinite pronouns. They have a sense of "referring back", but the person or thing to which they refer has not previously been explicitly named. English example: I know what I like.
• Interrogative pronouns ask which person or thing is meant. English example: Who did that?
• In many languages (e.g., Czech, English, French, Interlingua, Russian) the sets of relative and interrogative pronouns are nearly identical. Compare English: Who is that? (interrogative) to I know who is that. (relative).