as,when和while的区别

1、When，as和while的区别,when/as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。 when/as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。 Sorry, I was out when(as) you called me. He can write only when(as/while) the baby is asleep,when 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； as,while

2、 则是同时发生。 When /While /As she was making a phone call，I was writing a letter. Strike the iron while it is hot. Tom was disappointed that most of the guests had left when he arrived in the party.,when和while 还可作连词。 when表示“在那时(突然)”常用句型 be doing when be about to do when I was eating with my wife and chil

3、dren when we heard a loud noise While可表示“而，却”，表对比。 He likes her while she likes him. as常表示“随着”；“一边，一边” As autumn approaches, it is getting colder. The little girls sang as they went.,5. as 还可以表示原因（because,for） I didnt visit U as I know you were not at home 6.还可以用于倒装结构中，表示尽管 形、副词+as+主+谓，主句 名词(前不加冠词)+

4、as+主+谓，主句 Young as he is, he knows a lot. Child as he is, he knows a lot.,1.（2007山东）_I really dont like art， I find his work impressive. A. As B. Since C. If D. While 2. （2007四川）Id like to study law at university _my cousin prefers geography. A. though B. as C. while D. For 3. （2007重庆） _ ，his idea w

5、as accepted by all the people at the meeting. A. Strange as might it sound B. As it might sound strange C. As strange it might sound D. Strange as it might sound,D,C,D,4.（2006广东）Jenny was very sad over the loss of the photos she had shot at Canada， _this was a memory she especially treasured. A. as B. if C. when D. Where 5. （2006湖南）I had just stepped out of the bathroom and was busily drying myself with a towel _I heard the steps. A. while B. when C. since D. after 6. （哪个不对）-Im going to the pos