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 shortwhileago.
(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 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)
While he was tired,he would have a rest.
(他累了就休息一会儿。)
(while引导时间状语从句)
2.while引导让步状语从句时,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 lef twhen 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。)