Question

In which sentence is the underlined prepositional phrase an adverb phrase?

Answer 1

The sentence in which the underlined prepositional phrase is an adverb phrase is the following one: Astronomers discovered a quasar 12 billion light years away in 1991.  A prepositional phrase can function as an adjective, as an adverb or as a noun. When prepositional phrases function as an adverb phrase, they indicate the relantionship between the object of the preposition and the verb.

In this case, the object of the preposition (the NP "1991") is related to the verb ("discovered") and it answers the question "when" as regards the time in which the discovery took place.

Answer 2

Answer:

D). Astronomers discovered a quasar 12 billion light years away in 1991.

Explanation:

A Prepositional phrase comprises of a preposition followed by an object(that could be a pronoun or noun, etc. and it's modifier. This phrase usually functions either as an adjective or as an adverb. As per question, the sentence among the given options that carries a prepositional phrase functioning as an adverb phrase is displayed through option D as it contains the prepositional phrase('away in 1991') that modifies the verb 'discovered' and also answers the question 'when?'. Therefore, option D is the correct answer.