In linguistics and grammar, a pronoun (glossed PRO) is a word or a group of words that one may substitute for a noun or noun phrase.
Pronouns have traditionally been regarded as one of the parts of speech, but some modern theorists would not consider them to form a single class, in view of the variety of functions they perform cross-linguistically. An example of a pronoun is "you", which can be either singular or plural. Sub-types include personal and possessive pronouns, reflexive and reciprocal pronouns, demonstrative pronouns, relative and interrogative pronouns, and indefinite pronouns.
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