Question

In which sentence is the underlined phrase an adjective prepositional phrase? Robert Fulton’s invention of the steamboat gives him a prominent place in the history of transportation. Robert Fulton was born in 1765 in Lancaster County, Pennsylvania. Robert Fulton sailed on the Seine River in a small paddle wheel boat. In 1807, the steamboat Clermont traveled from New York City to Albany in 32 hours.

Answer 1

The answer to your question would be that the underlined phrase that is an adjective prepositional phrase is the following one: Robert Fulton's invention of the steambot gives him a prominent place in the history of transportation.

Prepositional phrases can function in three ways: they can function as a noun, an adjective, or as an adverb. When the prepositional phrase functions as an adjective, it gives us additional information about a noun or pronoun in the sentence. It tells us which one, what kind, or how many.

If the object of the preposition is related to another noun or pronoun, then the prepositional phrase is functioning as an adjective. In this case, "the steambot" (object of the preposition) is related to the "invention" (another noun), it is the invention by Robert Fulton.

Answer 2

Since you can't show underlining here, I will just discuss where in the sentences you can find an adjective prepositional phrase:
1) Robert Fulton’s invention of the steamboat gives him a prominent place in the history of transportation.
Here the prepositional phrases are: "of the seamboat" "in the history" and "of transportation"



2)Robert Fulton was born in 1765 in Lancaster County, Pennsylvania.
no adjective prepositional phrase here!

3) Robert Fulton sailed on the Seine River in a small paddle wheel boat.
no adjective prepositional phrase here!

4) In 1807, the steamboat Clermont traveled from New York City to Albany in 32 hours. no adjective prepositional phrase here either!