whenwhileas讲解与练习.doc

时间状语从句讲解与练习 when, while 和 as 引导时间状语从句的用法这三个词的意思很简单，都有“当时候”的意思, 但又有区别。一、when 的用法观察下面的句子:1. When he was a child he was always trying out new ideas. 他小时候就常常试验一些新的设想。 2. When she came into my room, I was just reading a book. 她走进我房间时，我正在看书。3. Were you writing when the teacher came in? 老师进来的时候，你在写信吗？4. Sorry, I was out when you called me. 对不起，你打电话来的时候我出去了。5. He was leaving when someone knocked at the door. 他正要走，这时有人敲门。 6. I thought of it just when you opened your mouth. 就在你要说话的时候，我也想到了。 根据以上的例句，我们可以总结出一点：when 从句中的A事件，相当于主句中B事件发生的时间点。也就是说，when 从句的重点不在动作本身发生的状态，而只是把它作为一个时间点，所以when从句多数情况下用的是一般过去时，而不用进行时, 而且, when 从句的动词大多是短暂性动词。这种说法也可以参照。实际上，when 从句也可以有其它的时态，但几乎也不用进行时，因为它也只是作为一个时间参照点。例如：When the manager comes here for a visit next week, Ill talk with him about this. 下周，经理来这参观时，我会和他谈谈此事。 When的特殊用法：主句（进行时）when 从句（一般时）I was walking along the street when a ball hit me on the head.我正沿着路边着，就在这时一个球打在了头上。此句中的when=at that time, 表示“突然性”二、while 的用法 while 从句的侧重点在于描述动作正在发生的状态，它的意思是：当while 事件正在发生的时候，另一件事如何如何。所以，while 从句一般用的是正在进行时。而另一件事的状态没有硬性的要求，根据具体情况而定。例如：1. While my wife was reading the newspaper, I was watching TV. 当妻子正在看报纸的时候，我正在看电视。2. While Jim was mending his bike, Lin Tao came to see him. 正当吉姆修自行车时，林涛来看他。3. While they were talking, the bell rang. 正在他们谈话的时候，上课铃响了。4. You cant do your homework while youre watching TV. 你不能看着电视做着作业。 从时间的角度来看，while 表示的是一段时间，是一个过程。这是while 的侧重点。因此，如果含有“一段时间”的含义的时候，就可以用while。例如： Strike while the iron is hot. 趁热打铁。这句话中，是说趁着铁是热的这段时间，赶紧打铁。再例：Im going to the post office. While youre there, can you get me some stamps? while的特殊用法：表示微弱的对比性转折“而”I like English while my sister likes math.我喜欢英语而我姐姐喜欢数学。三、as 的用法as从句表达的事件，往往只是主句动作发生的背景或条件时，也就是说，主句的动作是伴随着as从句中的动作发生的。因此，as 从句一般可以翻译成“边边”，或者“随着”之意。但与 while 从句不同的是，as 从句用的一般不用正在进行时，而只是一般过去时。例如：1. As my mother sang those old songs, tears ran down her cheeks. 当我妈妈唱起那些老歌时，眼泪顺着她的脸颊流了下来。 2. The students took notes as they listened. 学生们边听课边做笔记。3. The little girls sang as they went. 小姑娘们一边走，一边唱。4. As the time went on，the weather got worse. 随着时间的推移，气候更加糟糕。少数情况下，如果强调动作正在发生，as 从句也可以用正在进行时。这只能算是特例了。1. The sad mother sat on the roadside, shouting as she was crying. 伤心的妈妈坐在路边，边哭边叫喊。 2. As we were going out, it began to snow. 正当我们出门时，雪开始下起来。3. He came in as I was going to bed. 我正要上床睡觉，他进来了。四、when, while, as 的互换如果从句动作和主句动作同时发生，并且从句动作为延续性动词时，when，while，as 可以互换使用。这种情况下，它们的细微区别恐怕连英、美人自己也说不清了。1. When /While /As we were dancing, a stranger came in. 当我们跳舞时，一位陌生人走了进来。 dance 为延续性动词2. When /While /As she was making a phone call, I was writing a letter. 当她在打电话时，我正在写信。 make为延续性动词3. While/When/ As I was walking down the street, I noticed a police car in front of the bank. 我顺着马路往前走时，发现银行门前停着一辆警车。Until的用法 Until，直到.如果主句是肯定形式，表示的意思是“做某事直至某时”，动词必须是延续性的。如果主句是否定形式，表达的意思是“直至某时才做某事”。动词为延续性或非延续性都可以。正确使用这两个连词的关键之一就在于判断句中的动词该用肯定式还是否定式。肯定句：I slept until midnight. 我一直睡到半夜。 Wait until I call you. 等着我叫你。否定句：She didnt arrive until 6 oclock. 她直到6点才到。 Dont get off the bus until it has stopped. 公共汽车停稳后再下车。 as soon as的用法as soon as表示“一就”的意思。 例如： As soon as I got home, it began to rain. 我一到家天就开始下雨了。 Ill tell him as soon as he comes. 练习：在下列各句的空格中填入适当的连词1_ he comes tomorrow, I shall ask when he was born. 2_ he was speaking, everybody listened carefully. 3It was already eight oclock _ we got there. 4Have a good look at that man _ you pass him. 5I waited _ he came back. 6. I was about to go out _ a visitor came. 7The thieves ran away _ they saw the police. 8. He learned to speak German _ he was in Berlin.9. She likes everything to be ready _ she starts to work. 10. We played outside till sunset, _ it began to rain。11. _ she grew older, she became more responsible.