A preposition is a word which is used with a noun and also with a pronoun. Its function is to depict how the person or the thing, which is denoted by a noun or pronoun, stands in relation to something else.
SOME IMPORTANT PREPOSITIONS:
Following are enlisted important prepositions:
By, under, of, in, beside, among, up, down, off, over, from, on, at, for, through, till, to, out, with, about, above, across, along, around, before, behind, beneath, amongst, below, between, beyond, inside, outside etc.