Answer:
1. Madeline wanders in a distant hallway while looking at the horizon in despair. (COMPLEX SENTENCE)
1. Madeline wanders in a distant hallway although her feet can't take the route anymore. (COMPOUND-COMPLEX SENTENCE)
2. usher sings a melancholy song with an unknown melody, although the meaning was clear. (COMPLEX SENTENCE)
2. usher sings a melancholy song while the wind beat the window. (COMPOUND-COMPLEX SENTENCE)
Step-by-step explanation:
A complex sentence is one that has an independent sentence (which is a sentence that has meaning in its own right and does not need a complement to have meaning) linked to a dependent sentence (which is a sentence that has no meaning alone and needs a complement) to make sense) through a conjunction, adverb, relative pronoun, or other.
A compound-complex sentence is a sentence that has two or more independent sentences linked together by conjunctions, or by commas.