1、when與while引導(dǎo)時(shí)間狀語(yǔ)從句的區(qū)別第1頁(yè)，共19頁(yè)。（一）含義及構(gòu)成 過去進(jìn)行時(shí)表示過去某一時(shí)刻或某一段時(shí)間正在進(jìn)行或發(fā)生的動(dòng)作，其結(jié)構(gòu)為：was / were + v. ing。I/He/She/It was +v-ing (第一三人稱單數(shù)用was)We/You/They +v-ing 過去進(jìn)行時(shí)第2頁(yè)，共19頁(yè)。（1）過去進(jìn)行時(shí)的否定句結(jié)構(gòu)為：was / were+ not +v. -ing ，was與not?？s寫為wasnt，were與not?？s寫為werent。（2）過去進(jìn)行時(shí)的一般疑問句結(jié)構(gòu)為：Was / Were +主語(yǔ)+ v. -ing+其他？（3）過去進(jìn)行時(shí)的特殊疑問句

2、結(jié)構(gòu)為：疑問詞+ was / were+主語(yǔ)+v. -ing+其他？第3頁(yè)，共19頁(yè)。（二）用法 1. 表示過去某一時(shí)刻或某一段時(shí)間正在進(jìn)行或發(fā)生的動(dòng)作。與過去某一特定的時(shí)間狀語(yǔ)連用，常見的有：at 3 oclock yesterday afternoon, in those days, at this time yesterday等。 2. 表示過去一個(gè)動(dòng)作發(fā)生時(shí)，另一個(gè)動(dòng)作正在進(jìn)行，持續(xù)時(shí)間長(zhǎng)的動(dòng)作用過去進(jìn)行時(shí)，常用在while引導(dǎo)的時(shí)間狀語(yǔ)從句中。第4頁(yè)，共19頁(yè)。. 用所給詞的適當(dāng)形式填空1. I _ (help) my mother with housework at ten ocl

3、ock last Sunday. 2. The girl _ (have) a piano lesson at this time yesterday. 過去進(jìn)行時(shí)的用法was helpingwas having第5頁(yè)，共19頁(yè)。3. They _ (talk) about the film when the teacher came in. 4. While he _ (wait) for the bus, he read a newspaper. 5. He said he was _ (leave) for Shanghai soon.were talkingwas waitinglea

4、ving第6頁(yè)，共19頁(yè)。. 句型轉(zhuǎn)換1. Kate was drawing pictures when her mother came back. （改為否定句）Kate _ _ pictures when her mother came back. 2. She was babysitting her sister at this time yesterday. （改為一般疑問句）_ she _ her sister at this time yesterday?wasnt drawingWas babysitting第7頁(yè)，共19頁(yè)。3. They were having a party

5、 when I knocked at the door. （就劃線部分提問）_ _ they _ when you knocked at the door?What were doing第8頁(yè)，共19頁(yè)。. 用when或while填空1. What were you doing _ the earthquake happened? 2. _ I was shopping in the supermarket, I met my friend Nancy. whenWhile第9頁(yè)，共19頁(yè)。3. I was sleeping _ my cousin came to see me. 4. My

6、mother was doing the housework _ I was doing my homework. 5. _ the alien was in the shop, the girl called the police.when whileWhile第10頁(yè)，共19頁(yè)。when and whileBoth of them mean ”當(dāng)?shù)臅r(shí)候”.Are they the same? No ！第11頁(yè)，共19頁(yè)。when引導(dǎo)的時(shí)間狀語(yǔ)從句可以表示一個(gè)時(shí)間點(diǎn),也可以表示一個(gè)時(shí)間段。從句中可以用短暫性動(dòng)詞,也可以用延續(xù)性動(dòng)詞。從句中的動(dòng)作既可與主句的動(dòng)作同時(shí)發(fā)生，又可在主句的動(dòng)作之前或

7、之后發(fā)生。It was snowing when we got to the airport. 我們到達(dá)機(jī)場(chǎng)時(shí), 天正下著雪。My key dropped on the ground when I was walking in the park. 我在公園散步時(shí), 鑰匙掉在了地上。when第12頁(yè)，共19頁(yè)。whilewhile引導(dǎo)的時(shí)間狀語(yǔ)從句常指一個(gè)時(shí)間段,從句中的動(dòng)詞必須為延續(xù)性動(dòng)詞。while有時(shí)還可表示主句的動(dòng)作與從句的動(dòng)作同時(shí)發(fā)生。While he was reading, the phone rang. 他正在看書時(shí), 電話鈴響了。 Some students were read

8、ing while others were writing. 一些學(xué)生在讀書, 另一些學(xué)生在寫字。 第13頁(yè)，共19頁(yè)。tips:當(dāng)時(shí)間狀語(yǔ)從句中的動(dòng)作與主句中的動(dòng)作同時(shí)發(fā)生，且從句動(dòng)作為延續(xù)性動(dòng)詞時(shí)，when 與while都可以使用。when 說明從句的動(dòng)作各主句的動(dòng)作可以是同時(shí)發(fā)生，也可以是先后發(fā)生，while則強(qiáng)調(diào)主句的動(dòng)作在從句動(dòng)作的發(fā)生過程中發(fā)生或者主從句動(dòng)作同時(shí)發(fā)生。第14頁(yè)，共19頁(yè)。tips:通常情況下when能替代while, 但while不能替代when.當(dāng)從句和主句都用過去進(jìn)行時(shí)的時(shí)候，多用while引導(dǎo)。第15頁(yè)，共19頁(yè)。 (2009四川瀘州) What were y

9、ou doing _ Zhang Fan came in? A. when B. while C. where【解析】三個(gè)選項(xiàng)分別意為“當(dāng)時(shí)”、“與同時(shí)”、“哪里”，結(jié)合題意“當(dāng)張凡進(jìn)來時(shí)，你正在做什么？”可排除B、C二項(xiàng)，故選A。第16頁(yè)，共19頁(yè)。1. What _ (be) you _ (do) when he arrived?2. Jim_ (sleep) when I came in.3. They _ (watch) TV at 8:00 yesterday evening.4. Now he _ (read) and _. were doing was sleeping were

10、 watching is reading writingA. Fill in the blanks with the given words.第17頁(yè)，共19頁(yè)。B. Translate these sentences into English.1. 上課鈴響時(shí)，你在干什么？ What _ you _when the class bell rang? 2. 當(dāng)我媽媽進(jìn)來時(shí)我正在看書。 I _when my mother came in. 3. 昨天晚上十點(diǎn)鐘她正在做飯。 She _ at ten oclock _.weredoingwas readingwas cookinglast night / yesterday