Answer:
Before I was able to fall asleep
Explanation:
Identify the complete adverb clause in the following sentence.
Before I was able to fall asleep, I had to wake up my sister who was snoring.
Before I was able to fall asleep
An Adverb clause is a group of words that works as an adverb, that is, it modifies adjectives, verbs and adverbs. They are introduced by conjunctions. In this case we have the word "before". which is an adverbial clause of time.
"Before I was able to fall asleep" tells us the time the speaker was making reference to . He had to wake up his sister who was snoring before he could sleep.
