while的前后時態(tài)

當(dāng)while表示同時的時候，主句和從句的時態(tài)是一致的，既可以都是一般現(xiàn)在時，又可以都是一般過去時。可以表示過去同時發(fā)生或者現(xiàn)在正在同時發(fā)生某事。

while的具體用法

1、“當(dāng)……時候”，引導(dǎo)時間狀語從句(從句動作必須是延續(xù)性的)。

Please don't talk so loud while others are working.

While I was cleaning the window，my finger was seriously cut。

2、“雖然，盡管”相當(dāng)于although，引導(dǎo)讓步狀語從句(常把while放在句首)。

While she is a top student， she has some shortcomings. While the Internet is bridging the distance between people， it may also be breaking some home or will cause other family problems。

3、“只要，如果”等于as long as，引導(dǎo)條件狀語從句。

There is hope while there is life. While you study hard， your effort will pay off。