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同学们应该不难在英语考场上发现 while的身影,那么,对于它的用法我们可不能只知其一,而不知其二。今天我们就将 while的用法“一网打尽”,希望同学们都能对它有一个全面的了解。
一、 while用作名词时,意为“一段时间,一会儿”。例如:
I stayed there for a short while. 我在那儿呆了一小会儿。
The postman came a short while ago. 邮递员刚刚来过。
二、 while用作连词时,有以下几种含义:
1.意为“当……时候,和……同时”,引导时间状语从句。例如:
While I was watching TV, the bell rang. 我看电视时,铃响了。
Meimei watched TV while she ate her supper. 梅梅边吃晚饭边看电视。
2.意为“虽然,尽管”,引导让步状语从句。例如:
While it was late, he went on working. 虽然很晚了,但他还在继续工作。
While he is in poor health, he works hard. 虽然他身体不好,但他还是努力工作。
3.连接两个并列句子,表示“对比”关系。例如:
He went out for a walk, while I stayed at home. 他出去散步了,而我却呆在家里。
I like singing while she likes dancing. 我喜欢唱歌,而她喜欢跳舞。
You like sports, while I prefer music. 你喜欢体育,而我更喜欢音乐。
三、 while引导状语从句时,应注意以下几点:
1. while引导的时间状语从句既可放在句首,也可放在句末;而 while引导的让步状语从句一般放在句首,不放在句末。另外,也可以从意义上加以区分。例如:
While he was tired, he would have a rest. = He would have a rest while he was tired. 他累了就休息一会儿。( while引导时间状语从句)
While he was tired, he went on working. 虽然他累了,但他还是继续工作。( while引导让步状语从句)
2. while引导让步状语从句时,相当于 although;如果从句的主语和主句的主语相同,那么从句的主语和谓语动词 be都可以省略。例如:
While he was ill, he went there. = While ill, he went there. 虽然他有病,但他还是去那里了。
3. while和 when都可以引导时间状语从句,但应注意: while引导的时间状语从句中的谓语动词必须是延续性的动词;而 when引导的时间状语从句中的谓语动词既可以是延续性动词,也可以是非延续性动词。当时间状语从句中的谓语动词是延续性动词时, while和 when可以互相替换。例如:
While we were talking, the teacher came in. 我们正在谈话时,老师进来了。
The bus had left when we arrived at the bus stop. 当我们到达车站时,公共汽车已经开走了。( arrive是非延续性动词,因此,此句中的 when不能用 while替换。)
When/ While we were having a meeting, our teacher came in. 我们正在开会时,老师走了进来。( have是延续性动词,因此,句中的 when可以用 while替换。)
4. while引导的状语从句还可以表示“某个动作正在进行的同时,另一个动作也在进行之中”。例如:
While the teacher was speaking, the students were listening. 老师讲课时,学生们在听。
While he was writing, I was reading. 他写字时,我在看书。