Answer: "While you were sleeping, I watched a movie" is a complex sentence.
Explanation: A complex sentence is made up of an independent clause and a dependent clause. While an independent clause can stand alone as a sentence, a dependent clause cannot do this because it does not express a full idea. Moreover, dependent clauses are always introduced by a subordinating conjunction. <u>"While you were sleeping, I watched a movie" is a complex sentence because it includes a dependent clause</u> ("While you were sleeping") <u>and an independent clause </u>("I watched a movie"). <u>"While you were sleeping"</u> is a dependent clause because<u> it does not express a complete idea </u>and it has been <u>introduced by the subordinating conjunction "while"</u>.
