He is good at maths and it won’t be long he works out the problem. A. since B. u
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He is good at maths and it won’t be long ____ he works out the problem.
A. since B. until C. before D. when
试题答案
C
He is good at maths and it won’t be long ____ he works out the problem.
A. since B. until C. before D. when
C