英语和汉语有很大的区别，今天来谈一谈单词when和while的区别。主要区别有四点如下：
主要区别
1、when是at or during the time that,既指时间点,也可指一段时间,while是during the time that,只指一段时间,因此when引导的时间状语从句中的动词可以是终止性动词,也可以是延续性动词,而while从句中的动词必须是延续性动词.
3、由when引导的时间状语从句,主句用过去进行时,从句应用一般过去时；如果从句和主句的动作同时发生,两句都用过去进行时的时候,多用while引导,如：a.When the teacher came in,we were talking.当此句改变主从句的位置时,则为：While we were talking,the teacher came in.b.They were singing while we were dancing.
