as-when和while的區(qū)別PPT課件

1、2021/6/71When，as和while的區(qū)別 when/as是是at or during the time that, 既指時(shí)間點(diǎn)，既指時(shí)間點(diǎn)，也可指一段時(shí)間；也可指一段時(shí)間； while是是during the time that，只指一段時(shí)間。，只指一段時(shí)間。 when/as引導(dǎo)的時(shí)間狀語(yǔ)從句中的動(dòng)詞可以是引導(dǎo)的時(shí)間狀語(yǔ)從句中的動(dòng)詞可以是終止性終止性動(dòng)詞動(dòng)詞，也可以是，也可以是延續(xù)性動(dòng)詞延續(xù)性動(dòng)詞， 而而while從句中的動(dòng)詞必須是從句中的動(dòng)詞必須是延續(xù)性動(dòng)詞延續(xù)性動(dòng)詞。 Sorry, I was out when(as) you called me.He can write onl

2、y when(as/while) the baby is asleep2021/6/72 when 說(shuō)明從句的動(dòng)作和主句的動(dòng)作可以是同時(shí)，說(shuō)明從句的動(dòng)作和主句的動(dòng)作可以是同時(shí)，也可以是先后發(fā)生；也可以是先后發(fā)生； as,while 則是同時(shí)發(fā)生。則是同時(shí)發(fā)生。 When /While /As she was making a phone call，I was writing a letter.Strike the iron while it is hot. Tom was disappointed that most of the guests had left when he arrived

3、 in the party.2021/6/73when和和while 還可作連詞。還可作連詞。when表示表示“在那時(shí)在那時(shí)(突然突然)”常用句型常用句型be doing when be about to do when I was eating with my wife and children when we heard a loud noiseWhile可表示可表示“而，卻而，卻”，表對(duì)比。，表對(duì)比。He likes her while she likes him.as常表示常表示“隨著隨著”；“一邊一邊，一邊，一邊”As autumn approaches, it is getting

4、 colder.The little girls sang as they went.2021/6/745. as 還可以表示原因（還可以表示原因（because,for）I didnt visit U as I know you were not at home6.還可以用于倒裝結(jié)構(gòu)中，表示盡管還可以用于倒裝結(jié)構(gòu)中，表示盡管形、副詞形、副詞+as+主主+謂，主句謂，主句名詞名詞(前不加冠詞前不加冠詞)+as+主主+謂，主句謂，主句Young as he is, he knows a lot.Child as he is, he knows a lot.2021/6/751.（2007山東）山

5、東）_I really dont like art， I find his work impressive.A. As B. Since C. If D. While2. （2007四川）四川）Id like to study law at university_my cousin prefers geography.A. though B. as C. while D. For3. （2007重慶）重慶） _ ，his idea was accepted by all the people at the meeting.A. Strange as might it sound B. As i

6、t might sound strangeC. As strange it might sound D. Strange as it might soundDCD2021/6/764.（2006廣東）廣東）Jenny was very sad over the loss of the photos she had shot at Canada， _this was a memory she especially treasured.A. as B. if C. when D. Where5. （2006湖南）湖南）I had just stepped out of the bathroom and was busily drying myself with a towel _I heard the steps.A. while B. when C. since D. after6. （哪個(gè)不對(duì)）（哪個(gè)不對(duì)）-Im going to the post office.