A preposition is always part of a prepositional phrase. In some sentences the preposition tells more about the action. Each of these phrases answers the question where?
The dog ran down the street. Down the street tells where the dog ran.
Susan rode up the escalator. Up the escalator tells where Susan rode.
I put my coat in the closet. In the closet tells where I put the coat.
John sat on the park bench. On the park bench tells where John sat.
In each of these sentences, the prepositional phrase gives more information about the action in the sentence.
Use a prepositional phrase to tell more about the action in a sentence. The prepositional phrase may tell where something is happening.
▶It’s your turn. Find the prepositional phrase in this sentence that tells where something is happening. Mom set the groceries on the counter. Did you find the phrase? Good for you!