关系代词的省略

问题描述:

关系代词的省略
Each time _ they met,they would talk long hours together.
A.which B.during
C.when D./
D
为什么?

they met是修饰time的,所以是个定语从句
定语从句的先行词如果有不定代词时,不用which ,只能用that
又因为that 在从句中不充当成分
可以省略
所以选D