A preposition is a word that expresses relationships between people, places and things. They help us to understand a time, way or positional connection between two or more things.
Using them in your writing helps your reader to imagine your Setting and how things move within that setting effectively.
Positional Prepositions – Above the pool loomed the diving board.
Time Prepositions – They were married 7 years after they met.
Directional Prepositions (the way something is done) – They watched without speaking.
More then one word… – We sat next to each other.