6). since “自从...” ,主句常用现在完 成时,从句常用一般过去时
We have been friends ever since we met at school. 我们自从在学校认识至今一直是朋友。
常用句型“ It is/ has been + 时间段+ since 从句”译为“自从…多长时间了”
while 的特殊用法 while 可用于对比,意为“然而” e.g. I prefer black tea, while he likes coffee.
PRACTICE
1. We were swimming in the lake _A_____ suddenly the storm started.
It is three years since she joined the army.
时间状语从句其它引导词:
the moment, the minute, every time, each time, by the time, the day等,也可引导一个时间状语从句。
The day he returned home, his father was already dead.
1.连接词when, while, as 的用法区别
连接词类别 作 用
as
as 从句中动词是延续性时,侧重表示主从句动作 同时发生,意为“一边…一边…”
whenBiblioteka 强调动作的先后性,从句动词可以是延续性动词也 可以是非延续性动词。
while
强调动作的持续性及同时性,从句常用延续性动词 。
用while, when填空:
A. when B. while before
C. until D.