TASK DEFINITION: Given scientific fact as input, generate the question from this fact such that it can be answered from the input.
PROBLEM: Compounds containing an atom of nitrogen element, bonded in a hydrocarbon framework, are classified as amines.

SOLUTION: Compounds containing an atom of what element, bonded in a hydrocarbon framework, are classified as amines?

PROBLEM: Gastric emptying is regulated by both the stomach and the duodenum.

SOLUTION: Gastric emptying is regulated by both the stomach and what other digestive structure?

PROBLEM: Gases in the air allows us to hear sound.

SOLUTION:
What in the air allows us to hear sound?