Hebecameanactorataveryyoungagebutitwasnearly20years

问题详情：

 He became an actor at a very young age but it was nearly 20 years ______ he became famous.

    A. until                       B. when                     C. before                   D. that

【回答】

 C     句型：It’s /will be +时间段 before +从句：过了多久才……

知识点：连词

题型：选择题