What are examples of prepositional phrases?

at the doorof beautyduring the Victorian era

Prepositional phrases consist of the preposition and its object. My mother and father's love story started during the Victorian era.during = prepositionthe Victorian era = object The object is found right after the preposition.

and particles are often confused. To avoid confusion, make the phrase the first words in the sentence. Example: Luffy passed by the Fishman Island. At first glance, you would think that by the Fishman Island is a prepositional phrase but it isn't. To check it, move the said phrase before the subject which is Luffy. By the Fishman Island Luffy passed. Does it make sense? No. Therefore, by is not a preposition.