Question

2.    the delayed flight will take off depends much on the weather.

A. Why   B. When

C. That   D. What

Answer 1

2.    B考查名词性从句。句意：延误了的航班将何时起飞主要取决于天气。所填词引导主语从句，在从句中作时间状语，用when,故选B。