Is next to a prepositional phrase?

"Next to" is not a prepositional phrase on its own. It is a prepositional phrase.

Here's why:

* Prepositional phrases consist of a preposition followed by its object.

* "Next to" is the preposition, and the object is the noun or pronoun that follows it.

For example:

* "Next to the house" is a prepositional phrase.

* "Next to her" is a prepositional phrase.

You can't use "next to" as a standalone phrase without an object to indicate location or position.