What do you call a group of words that acts like an adverb?

noun phrase

prepositional phrase

adverbial clause

adverbial phrase

Adverbial clause should be the answer

The correct answer is adverbial clause.

An adverbial (adverb) clause is a group of words that function as an adverb in a sentence.

Adverb clauses add information that elaborates on when, where, why, how the action in the sentence takes place.

An adverb clause must contain a subject and a verb to be complete.

An adverb clause can be used at the beginning of a sentence:

Before you do your homework, go and see your sister.

They can also be placed at the end of a sentence:

The day felt lonely because nobody came to visit me.