1、 while1 用作名词时,意为一段时间,一会儿。比如:
I stayed there for a short while.

(我在那儿呆了一小会儿。)

The postman came2 a short while ago.

(邮递员刚刚来过。)

2、 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。比如:

While I was3 watching TV, the bell rang.

(我看电视时,铃响了。)

Meimei watched TV while she ate4 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。比如:

While it was late, he went on working.

(虽然非常晚了,但他还在继续工作。)

While he is in poor health5, he works6 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。比如:

He went out for a walk, while I stayed at home.

(他出去散步了,而我却呆在家。)

I like singing while she likes dancing.

(我喜欢唱歌,而她喜欢跳舞。)

You like sports, while I prefer7 music.

(你喜欢体育,而我更喜欢音乐。)

3、 while 引导状语从句时,应注意以下几个方面:

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别。比如:

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 would8 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,假如从句的主语和主句的主语相同,那样从句的主语和谓语动词 be 都可以省略。比如:

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需要是延续性的动词;而 when 引导的时间状语从句中的谓语动词既能够是延续性动词,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。比如:

While we were talking, the teacher came in.

(大家正在谈话时,老师进去了。)

The bus had9 left when we arrived at the bus sTOP.

(当大家到达车站时,公共汽车已经开走了。)

( arrive 是非延续性动词,因此,此句中的 when 不可以用 while 替换。)

When / While we were having a meeting10, our teacher came in.

(大家正在开会时,老师走了进去。)

( 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。比如:

While the teacher was speaking, the students were listening.

(老师讲课时,学生们在听。)

While he was writing11, I was reading12.

(他写字时,我在看书。)