Read the given query and classify it as a 'Good' or 'Bad' query depending on how well the query is formed, 'Bad' being the expected output for a not so well formed query and 'Good' being the expected output for a well formed query. A query may be wrong based on common sense or general facts, but if it is well formed, you should answer with Good.

Q: What causes opacity ?

A: Good
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Q: How do you explain cupid to a child ?

A: Good
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Q: What colors were used the most in Greek art ?

A:
Good
****