This document provides information about prepositions and their uses in the English language. It begins by defining a preposition as a word that precedes a noun or pronoun and indicates its relationship to another word. Examples of common prepositions that indicate location are given, such as "in, on, under, behind." The document then discusses specific uses of the prepositions "at, in, on" to indicate points, enclosed spaces, and surfaces. Further sections explain how prepositions can indicate time, movement, and relationship between objects. Examples of simple sentences using prepositions are provided to demonstrate their meaning in context.