when与while的区别和用法
whenwhile的用法口诀?
whenwhile的用法口诀?
when和while的区别在于引导时间状语从句的时候,while和进行时(一般现在时或过去进行时)连用。其余大部分情况下都用when,但是有的时候即便用了进行时,用when也是完全没问题的,所以大部分情况下when和while可以互换。可以用while的时候用when,但用when引导的句子换while的时候要进行具体情况而定
bedoingwhen和while的区别?
前者when侧重的是那个时间点,后者侧重的是同一时间。例如
I was reading a book when he came in.
I was cooking while I was singing loudly.
when和while放在句首与句中的区别?
①when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。
如:
Why do you want a new job when youve got such a good one already?(get为短暂性动词)你已经找到如此好的工作,为何还想再找新的?
Sorry,I was out when you called me.(call为短暂性动词)对不起,你打电话时我刚好外出了。
Strike while the iron is hot.(is为延续性动词,表示一种持续的状态)趁热打铁。
②when 说明从句的动作和主句的动作可以是同时,也可以是先后发生;while 则强调主句的动作在从句动作的发生的过程中或主从句两个动作同时发生。
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.
④when和while 还可作并列连词。when表示“在那时”;while表示“而,却”,表对照关系。如:
a. The children were running to move the bag of rice when they heard the sound of a motor bike. 孩子们正要跑过去搬开那袋米,这时他们听到了摩托车的声音。
b. He is strong while his brother is weak. 他长得很结实,而他弟弟却很瘦弱。