A preposition is a small word before noun or pronoun: in, on, at, after, to, with…

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Prepositions show the relationship between a noun or pronoun with other words in a sentence.

Please learn more about them in these topics:

Prepositions of time (in, on, at)

Prepositions of place (in, on, at)

Prepositions of movement (to, into, out of, on to, off, around, towards, away from, past, over, downstairs, upstairs)

Some prepositions you should learn more in details (until, by, according to, over)

Verbs and prepositions (pay for, borrow from, etc)

Adjectives and preposition (good at, addicted to, etc)