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

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

Question: The seven unique crystal types are defined by faces parts of themselves (parts that intersect at various angles).

Answer: The seven unique crystal types are defined by what parts of themselves (parts that intersect at various angles)?

Question: You call air flowing over earth's surface wind.

Answer:
What do you call air flowing over earth's surface?