A preposition is a word—and almost always a very small, very common word—that shows direction (to in "a letter to you"), location (at in "at the door"), or time (by in "by noon"), or that introduces an object (of in "a basket of apples"). Prepositions are typically followed by an object, which can be a noun (noon), a noun phrase (the door), or a pronoun (you).
Learn Prepositions by Photos.
Source: BDWORD
