Question

【题目】Bill won’t start the experiment until he ____ how to do it.

A. will show B. shows C. will be showed D. is showed

Answer 1

【答案】D

【解析】句意：比尔在演示如何做之前，他是不会开始实验的。考查一般现在时的被动语态。A. will show一般将来时；B. shows一般现在时；C. will be showed一般将来时的被动语态；D. is showed一般现在时的被动语态。Not…until…：直到…才…，在…以前不做…；主句用将来时，从句用一般现在时；结合句意和语境可知选D。