Given a statement, generate a question such that the answer is contained in that statement.

Q: People describes things with their appearance.

A: What do people describe things with?
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Q: Vinegar changes the color of litmus paper from blue to red

A: What color does Vinegar change the color of litmus paper from blue to?
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Q: Liquid is essential for all life in the world.

A:
What is essential for all life in the world?
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