题目

题型：不详难度：来源：

They kept trying _________ they must have known it was hopeless.

A．if

B．because

C．when

D．where

答案

C

解析

when 在此的意思不是"当……的时候"，而是"尽管"、"虽然"的意思。又如：He walks when he might take a taxi. 尽管他可以坐出租车，但他却走路。