Such crimes may be so complex that months or years go by before anyone them.A.di
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Such crimes may be so complex that months or years go by before anyone ________ them.
A.discovered
B.would have discovered
C.will discover
D.discovers
试题答案
D
句意：这样的犯罪可能非常复杂以至数月或数年的时间过去才会被人发现。before引导的时间状语从句用一般现在时表将来。