Sometimes, we do not want to use a noun. So, we use pronouns:

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     I am sure you have heard all these words in English more than once. Here you can learn the rules of how to use them.

Personal subject pronouns (I, you, he, she, it, we, you, they)

Personal object pronouns (me, you, him, her, it, us, you, them)

Possessive pronouns (mine, yours, his, hers, its, ours, yours, theirs)

Reflexive/intensive pronouns (myself, yourself, himself, herself, itself, ourselves, yourselves, themselves)

Demonstrative pronouns (this, that, these, those)

Reciprocal pronouns (each other, one another)

Indefinite pronouns (some, any, somebody, someone, somewhere, anybody, anyone, anywhere, nobody, no one, nowhere, either, neither, both, enough, several, all, every, many, much, none)

Interrogative pronouns (who, whom, whose, which, what)

Relative pronouns (who, whom, which, that, whose, whoever, when, what, where)