If you had _____ your test paper carefully before handing it in, you would have made fewer mistakes. 

A. looked up      B. thought about  C. gone over      D. gone round 

If you had ______your test paper carefully before handing it in, you would have made fewer mistakes.

A. looked up    B. thought about    C. gone over   D. gone round

If you had ______ your test paper carefully before handing it in, you would have made fewer mistakes.

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