Prepositional phrases consist of a preposition followed by its object (usually a noun or pronoun).
Examples of sentences without prepositional phrases:
* The dog barked.
* She laughed.
* He runs fast.
Examples of sentences with prepositional phrases:
* The dog barked at the mailman.
* She laughed at the joke.
* He runs fast on the track.
Prepositional phrases are used to add information about location, time, direction, or other relationships. While they are common in many sentences, they are not essential for every sentence to be grammatically correct.