when和while的区别是

Period____8______ in Unit ___6_________ （Period_____20_____Week 4-6）Subject _Grammar (B)

Teaching aims

To use the Past Continuous Tense with while and when correctly

Teaching interesting points of this class:

The differences of when and while in Past Continuous Tense

Teaching steps:

I. Cooperation and intercourse

1. Check the preparation

2. Discuss in groups

II. Question and explanation

Check the exercises on page 101, and explain the differences between when and while.

when和while的区别是：

when只能用于一般时态

while可以用于进行时态

when conj. 在...的时候, 当…的时候

when 在绝大多数情况下，所引导的从句中，应该使用非延续性动词（也叫瞬间动词）

例如：I'll call you when I get there. 我一到那里就给你打电话

I was about to go out when the telephone rang.我刚要出门，电话铃就响了。

但是，when 却可以be 连用。

例如：I lived in this village when I was a boy. 当我还是个孩子的时候我住在这个村庄里。

When I was young, I was sick all the time. 在我小时候我总是生病

while 当...的时候

While he was eating, I asked him to lend me $2. 当他正在吃饭时,我请他借给我二美元。While I read, she sang. 我看书时，她在唱歌。

while 的这种用法一般都和延续性动词连用

while 可以表示“对比‘，这样用有的语法书认为是并列连词

Some people like coffee, while others like tea. 有些人喜欢咖啡, 而有些人喜欢茶。

as 当...之时，一边......一边.......

I slipped on the ice as I ran home. 我跑回家时在冰上滑了一跤

He dropped the glass as he stood up. 他站起来时，把杯子摔了。

She sang As she worked. 她一边工作一边唱歌。

III. Rumination and evaluation

when, as, while这三个词都可以引出时间状语从句，它们的差别是：when 从句表示某时刻或一段时间as 从句表示进展过程，while 只表示一段时间

When he left the house, I was sitting in the garden.

当他离开家时，我正在院子里坐着。

When he arrived home, it was just nine o'clock.

当他到家时，正是九点钟。

As he grew older, he became more intelligent.

随着他年龄的增长，他变得更有才智了。

While he was in London,he studied music.

当他在伦敦时，他学习音乐。

While she was typing the letter,the telephone rang.

当她在用打字机打那封信时，电话响了。

IV. Consolidation and test

过去进行时巩固练习：

1. Simon _____________ (make) a model plane at 8:00 a.m.

2. Peter ______________(do) his homework at seven last night.

3. They ____________ (watch) a football match from 7:00 to 9:00 last night.

4． He _____________(try) to draw a plane on the blackboard at that time.

5． What book _______ you _______(read) when I _______ (see)you at four yesterday afternoon? 6． While she __________ (watch) TV, her son ____________ (play) outside the room.

7． It ________ (begin) to rain while we _____________(work) in the field.

8． I ________ (do) my homework last night when the light _______ (go) out. {go out 意外熄灭} 9．——I saw you in the reading room yesterday , Tom. What were you doing?

-----Oh, I ____________ (read) some books on science.

10. Girls ___________(dance) while boys ____________(sing) at the party.

11. --- Did you see Tim just now?

--- Yes. He __________ (fish) by the river.

12. When the teacher ______ (come) into the classroom, the students ____（laugh）loudly.

V. Guide to the preview

1. Revise the use of the Past Continuous Tense and make some sentences.

2. Discuss and make a project about natural disasters with your classmates.

教学反思：

When 与while的区别并不是通过一节课的讲解就能掌握的，要多练习才可以。区别并不难，正确使用才是关键。