Question

The students performed the play in the auditorium. Which is the prepositional phrase in this sentence?

Answer 1

In the auditorium is the prepositional phrase.

Specifies where, how, when and why.

Answer 2

The prepositional phrase is in the auditorium.

At minimum a prepositional phrase includes a preposition and a noun, pronoun, gerund, or clause as the object. Some common prepositions are at, by, in, at, to, etc... As an adverb, a prepositional phrase will answer the questions How?, When?, or Where? In this case, we can ask, "Where do the students perform?" The answer is in the auditorium.