Answer:
All the answers are in the explanation
Step-by-step explanation:
10. The classes were all held in the morning. : The prepositional phrase. It's an adverb. It's an adverb of time.
11. Work began promptly at nine o’clock. The prepositional phrase. It's an adverb. It's an adverb of time.
12. The students found the illustrations of the problem interesting and helpful. The prepositional phrase. The italicized words change the illustrations: It's an adjective.
13. Teachers located materials on different topics. The prepositional phrase. It's a mode adverb.
14. Classes like these kept the students busy. The prepositional phrase. It's a mode adverb.