Question

【题目】________ the delayed flight will take off depends much on the weather.
A.Why
B.When
C.That
D.What

Answer 1

【答案】B
【解析】句意：被延误的航班何时起飞依天气而定。题干中主句的谓语动词为depends，为此前面是主语从句。Why在主语从句中做原因状语；when在主语从句中作时间状语；that在主语从句中不做任何成分；what在主语从句中作主语或宾语。根据语境判断主语从句中缺少时间状语，故选B项。