QUESTION 1: An adverb clause will always contain a subject, a verb, and a subordinating conjunction.
Things can sometimes get a little bit confusing for students because, like an independent clause, the adverb clause (which is a dependent clause) will contain a subject and a verb. The way to distinguish adverb clause from independent clause is that the adverb clause will always be the clause that begins with the subordinating conjunction. The independent clause will never begin with one. Additionally, the adverb clause will be the clause that addresses when something is done, how something is done, where something is, or why something is done. That said, I have bolded the adverb clauses for each of the questions below.
QUESTION 2: Tommy scrubbed the bathroom tile until his arms ached.
QUESTION 3: Jojo's three dogs bolted
from the driveway once they saw her car
turn the corner.
QUESTION 4: When
the storm started, she was at the store.
(NOTE: When an adverb clause begins a sentence, it will always be followed by a comma.)