Question

what is the use of preposition

Answer 1

prepositions are usually used in front of nouns and pronouns and show the relationship between the noun in the pronoun and other words in a sentence.
hope it helps

Answer 2

A preposition is a word which expresses relationship of a noun or a pronoun to other words of the sentence

There are six types of preposition :

1) Preposition for Time

2) Preposition for Place

3) Preposition for Direction

4) Preposition for Agent

5) Preposition for Instrument

6) Prepositional Phrases