高考英语教案——when_while及as考点辨析

1、高考英语教案when_while及as考点辨析，及考点辨析when， while及as都能引导多种状语从句:一、 when常见考点1、“当时候”， 引导时间状语从句。When he was a young man， he was fond of hunting.It was already 10:00PM，when I finished the work.2、“正在那时，这时”等于and at that time，引导时间状语从句。We were having a meeting when someone broke in.Wewereabouttoleave when it began to

2、 rain.3、“既然”等于since 或considering that， 引导原因状语从句。It was foolish of you to take a taxi，when you should easily walk there in five minutes.How can they learn anything when they spend all their spare time watching TV?4、“虽然，然而，可是”引导让步状语从句。He usually walks when he might ride.They had only three chairs when

3、 they need five.二、 while常见考点1、“当时候”， 引导时间状语从句（从句动作必须是延续性的）。Please dont talk so loud while others are working.While I was cleaning the window， my finger was seriously cut.2、“虽然，尽管”相当于although，引导让步状语从句（常把while放在句首）。While she is a top student， she has some shortcomings.While the Internet is bridging th

4、e 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，引导条件状语从句。There is hope while there is life.While you study hard， your effort will pay off.4、“而，然而”，表对比或相反的情况。He likes pop music，while I am fond of folk music.Kids talk frequently ab

5、out what they can do，while many adults do the opposite， tending to talk about what they cant .三、 as常见考点1、“一边一边”或“随着”，引导时间状语从句（as引导的从句内部的动作与主句内动作同步）。John sings as he works. （一边一边）James blindness was getting worse as he was getting older.（随着）2、“因为”， 引导原因状语从句。As you werent there， I left a message.Perha

6、pshe will need some help as he was ill.3、“尽管，即使，虽然” 引导让步状语从句（用于形容词，副词或名词后构成部分倒装）。Young as I am， I already know what career I want to follow.Much as I like you， I couldnt live with you.Child as Tom is ， he has been a success.1.（2007山东，29）_I really dont like art， I find his work impressive.A. AsB. Sin

7、ceC. IfD. While2. （2007北京，25） Where is that report ?I brought it to you _you were in Mr Blacks office yesterday.A. ifB. whenC. becauseD. before3. （2007四川，29）Id like to study law at university_my cousin prefers geography.A. thoughB. asC. whileD. for4. （2007重庆，34） _ ，his idea was accepted by all the p

8、eople at the meeting.A. Strange as might it soundB. As it might sound strangeC. As strange it might soundD. Strange as it might sound5.（2006广东，26）Jenny was very sad over the loss of the photos she had shot at Canada， _this was a memory she especially treasured.A. asB. ifC. whenD. where6. （2006山东，31）

9、How can you expect to learn anything _you never listen?A. in caseB. even ifC. unlessD. when7. （2006湖南，31）I had just stepped out of the bathroom and was busily drying myself with a towel _I heard the steps.A. whileB. when C. since D. after8. （2006辽宁，24）He was about halfway through his meal _a familia

10、r voice came to his ears.A. whyB. whereC. whenD. while9. （2006天津，2） The cost of living in Glasgow is among the lowest in Britain， the quality of life is probably one of the highest.A. sinceB. whenC. asD. while10. （2005福建，24） Did Jack come back early last night? Yes. It was not yet eight oclock _he a

11、rrived home.A. beforeB. whenC. thatD. until11. （2005上海，34）He transplanted the little tree to the garden _it was the best time for it.A. whereB. whenC. thatD. until12. （2004全国I ，35）I do every single bit of housework， _my husband Bob just does the dishes now and then.A. sinceB. whileC. whenD. as13. （2

12、004全国 ，21）Dont be afraid of asking for help _it is needed.A. unlessB. sinceC. althoughD. when14. （2004浙江 ，31） _modeling business is by no means easy to get into， the good model will always be in demand.A. WhileB. SinceC. AsD. If15. （2004江苏 ，23） _I accept that he is not perfect， I do actually like th

13、e personA. WhileB. SinceC. BeforeD. UnlessThe key: 1-5DBCDA6-10DBCDB11-15BBDAA一、根据从句动作的持续性来区分 1、“主短从长”型：即主句是一个短暂性动作，而从句是一个持续性动作，此时三者都可用。如： Jim hurt his arm whilewhen， as he was playing tennis. 吉姆打网球时把手臂扭伤了。 AsWhen， While she was waiting for the train， she became very impatient. 她在等火车时，变得很不耐烦。 注意：as

14、用于引出一个持续性动词表示“在期间”时，其谓语通常只能是那些含有动作(action)和发展(development)意味的动词，一般不能是那些不用于进行时态的动词(如 be，seem，love，want，agree，see，know，have等)，所以下面一句中的 while 不能换为 as： A：Im going to the post office. 我要去邮局。 B：While you are there， can you get me some stamps？当你在邮局时，能帮我买几张邮票吗？ 2、“主长从长”型：即主句和从句为两个同时进行的动作或存在的状态，且强调主句动作或状态延续到

15、从句所指的整个时间，此时通常要用while。I always listen to the radio while Im driving. 我总是一边开车一边听收音机。但是，若主句和从句所表示的两个同时进行的动作含有“一边一边”之意时，则习惯上要用as。如：He swung his arms as he walked. 他走路时摆动着手臂。3、“主长从短”型：即主句是一个持续性动作，而从句是一个短暂性动作，此时可以用as或when，但不能用while。如：It was raining hard when as we arrived. 我们到达时正下着大雨。When As he came in,

16、I was listening to the radio. 他进来时，我在听收音机。二、根据主句与从句动作是否同时发生来区分1、若主句与从句表示的是两个同时发生的短暂性动作，含有类似汉语“一就”的意思，英语一般要用as (也可用when)。如：The ice cracked as when I stepped onto it. 我一踩冰就裂了。He jumped to his feet as the boss came in. 老板一进来他立刻站了起来。但是，在hardly scarcelywhen句式中，不能将when换成as。如：Scarcely had we arrived, when

17、it began to rain. 我们刚一到就下起雨来了。2、若主句与从句表示的是两个几乎同时发生的短暂性动作，含有类似汉语“刚要就”“正要却”的意思，英语一般要用as(也可用when)，且此时通常连用副词just。如：I caught him just when as he was leaving the building. 他正要离开大楼的时候，我把他截住了。Just as when the two men were leaving, a message arrived. 就在这两个人要离开的时候，突然有了消息。三、根据是否具有伴随变化来区分若要表示主句动作伴随从句动作同时发展变化，有类

18、似汉语“随着”的意思，英语习惯上要用as，而不用when或while。如：The room grew colder as the fire burnt down. 随着炉火逐渐减弱，房间越来越冷。As time goes by my memory seems to get worse. 随着时间的流逝，我的记忆力似乎越来越差。注：若不是引导从句，而是引出一个短语，则用with，不用as。如：With winter coming on, its time to buy warm clothes. 随着冬天到来，该买暖和衣裳了。The shadows lengthened with the app

19、roach of sunset. 随着太阳下落，影子也逐渐伸长。四、根据从句动作的规律性来区分若暗示一种规律性，表示“每当的时候”，英语一般要用when。如：Its cold when it snows. 下雪时天冷。He smiles when you praise him. 你夸奖他时他总是笑笑。五、根据主从句动作的先后顺序来区分若主句与从句所表示的动作不是同时发生，而是有先后顺序时，一般要用when。如：When he arrives hell tell us all about the match. 等他到了，他会好好给我们讲讲那场比赛的情况。When she had finished

20、 she waited as though for a reply. 她讲完之后等了等，仿佛是在等候回答似的。六、根据是否具有“趁机”意味来区分1、若从句所表示的“当的时候”具有“趁机”的意味，则通常用while。如：Strike while the iron is hot. 趁热打铁。I tried to slip the note to him while the teacher wasnt looking. 我想趁老师不注意时把条子偷偷递给他。有时也用when。如：He stole the money when no one was by. 他趁旁边无人时把钱偷走了。The boy looks at her repeatedly when shes not looking. 那男孩趁她没看他的时候不断地盯着她看。七、根据是否用作并列连词来区分when可用作并列连词，表示“这时