Final answer:
The phrase "on stilts" is a prepositional phrase in which "on" is the preposition and "stilts" is the noun, providing information about location or manner.
Step-by-step explanation:
The term "on stilts" is a prepositional phrase. In English grammar, a prepositional phrase begins with a preposition and usually ends with a noun or noun phrase. In this case, "on" is the preposition, and "stilts" is the noun, making "on stilts" the complete prepositional phrase.
Prepositional phrases often provide information about location, time, or direction. For instance, "The performers walked on stilts" shows the location or manner in which the performers walked. Prepositional phrases can also act as adverbials or can fill the role of a subject complement after a linking verb.