Write a correct answer to the given question based on its associated fact. Make sure that your answer is contained in the associated fact. Don't be creative and introduce any new word that is not mentioned in the associated fact! Remember that the associated fact has been rearranged to form the question. So, the correct answer words must lie within the associated fact. The correct answer can be a word, phrase, or even a sentence.

Q: Fact: moist air falls on the windward side of a mountain. 
Question: Where does moist air fall on a mountain?

A: windward side.
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Q: Fact: Water must not be polluted to be safe. 
Question: What can happen to water to make it unsafe?

A: Pollution.
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Q: Fact: fanning a fire keeps the fire burning. 
Question: What keeps a fire burning?

A:
fanning.
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