1、Unit 4 Grammar(1)时间状语从句：时间状语从句：引导时间状语从句的连词有：引导时间状语从句的连词有：when,while,as,before,after,till,until,since,as soon as,the moment,immediately,every time,next time,the first time,once 等。等。when,while,as表表“当当.时时”的异同的异同：相同点相同点:当从句的谓语是延续性动词时，三者常当从句的谓语是延续性动词时，三者常可互换可互换i.e.When/While/As we were still laughing,the
2、 teacher came in.不同点不同点:1)when既表既表“时间段时间段”又表又表“时间时间 点点”(=during or at the time that),从句中动从句中动词既可是终止性的，词既可是终止性的，也可是持续性的，也可是持续性的，还可表还可表“正在这时正在这时”i.e.(1).When I arrived there,they were watching TV.(2).When I was young,I liked singing and dancing.2)while只表只表“时间段时间段”(=during the time that),从句中从句中动词只限于持续性
3、动词，它有时含对照之意，表动词只限于持续性动词，它有时含对照之意，表“然然”而而i.e.(1)He fell asleep while he was studying his grammar book.3)as用法与用法与when相似，但它侧重动作的同时性，表相似，但它侧重动作的同时性，表“一边一边.一边一边.”，还表，还表“随着随着”i.e.(1)They talked as they walked.(2)As time goes by,we get wiser.1.when-正在正在的时候，突然的时候，突然 I was walking along the street when I met
4、 him.One evening,little Hans was sitting near the fire when he heard a loud knock at the door.I was about to fall asleep when my sister came in.He had just got back home when the telephone rang.我正准备告诉他那个秘密，这时有人拍了拍我的肩膀。我正准备告诉他那个秘密，这时有人拍了拍我的肩膀。I was about to tell him the secret when someone patted me
5、on the shoulder.I had hardly got home when it began to rain.Hardly had I got home when it began to rain.1.He transplanted the little tree to the garden _ it was the best time for it.A.where B.when C.that D.until2.-Did Jack come back early last night?-Yes.It was not yet eight oclock _ he arrived home
6、.A.before B.when C.that D.until3.He was about halfway through his meal _ a familiar voice came to his ears.A.why B.where C.when D.while1)The cost of living in Glasgow is among the lowest in Britain,_ the quality of life is probably one of the highest.A.since B.when C.as D.while2)_ I accept that he i
7、s not perfect,I do actually like the person.A.While B.Since C.Before D.Unless2.连接词连接词while的用法小结的用法小结 1)while引导的动作引导的动作必须是持续性必须是持续性的，侧重主句动作的，侧重主句动作和从句动作相对比。如：和从句动作相对比。如：Please dont talk so loud while others are working.2)while作为并列连词，意为作为并列连词，意为“而，却而，却”，表示对比。，表示对比。3)while可表示尽管，相当于可表示尽管，相当于although。1.W
8、hile I was waiting for Tom,three buses went by.2.I do every single bit of housework,while my husband Bob just does the dishes now and then.3.While modeling business is by no means easy to get into,the good model will always be in demand.when/while doing:1)When/While I was looking through the paper,I
9、 noticed a few grammatical mistakesWhen/While looking through the paper,I noticed a few grammatical mistakes.2)While he was wandering through the square,he caught sight of a snake-charmerWhile wandering through the square,he caught sight of a snake-charmerwhen/while doneWhen we were taken round the
10、city,we were impressed by the citys new look.When taken round the city,we were impressed by the citys new look.3.not until-直到直到才才 He didnt get off the bus until it stopped.Not until the bus stopped did he get off it.It was not until the bus stopped that he got off it.直到被送入手术间时，他才明白遵守交通规则的重要性。直到被送入手术
11、间时，他才明白遵守交通规则的重要性。He didnt realize the importance of observing the traffic regulations until he was sent into the operating room.1.-Was his father very strict with him when he was at school?-Yes.He had never praised him _ he became one of the top students in his grade.A.after B.unless C.until D.when
12、2.A good storyteller must be able to hold listeners curiosity _ he reaches the end of the story.A.when B.unless C.after D.until3.It was not _ she took off her dark glasses _ I realized she was a famous film star.A.when;that B.until;that C.until;when D.when;then小结：小结：till,until和和notuntil：1.until/till
13、引导时间状语从句用于肯定句时，主句的动词引导时间状语从句用于肯定句时，主句的动词 是是延续性动词，表示动作或状态一直持续到延续性动词，表示动作或状态一直持续到until/till所所 表示的表示的时间，意为时间，意为“某动作一直延续到某时间点才停止某动作一直延续到某时间点才停止”。如：。如：We waited until he came.2用于否定句时，主句谓语动词是非延续性动词，从句为肯用于否定句时，主句谓语动词是非延续性动词，从句为肯定，意为定，意为“某动作直到某时间才开始某动作直到某时间才开始”。如：。如：The boy wont go to bed till/until his mum
14、 returns.3till不可以置于句首，而不可以置于句首，而until可以。如：可以。如：Until you told me I had no idea of it.4notuntil句型中的强调和倒装说法：句型中的强调和倒装说法：It was not until you told me that I had any idea of it.Not until you told me did I have any idea of it.4.before-在在之前之前 He ran off before I could stop him.现在就做，免得你忘记了。现在就做，免得你忘记了。Do i
15、t now before you forget it.几个星期过去了我才意识到那幅画丢了。几个星期过去了我才意识到那幅画丢了。Several weeks had gone by before I realized the painting was missing.It was not long before I forgot it all.五年后我们才会再见面呢。五年后我们才会再见面呢。It will be five years before we meet again.我们将作进一步的讨论，然后再作出最终的结论。我们将作进一步的讨论，然后再作出最终的结论。We will have a fur
16、ther discussion before we draw/make a final conclusion.1.He made a mistake,but then he corrected the situation _ it got worse.A.until B.when C.before D.as2.Scientists say it may be five or six years _ it is possible to test this medicine on human patients.A.since B.after C.before D.when3.-Why didnt
17、you tell him about the meeting?-He rushed out of the room _ I could say a word.A.before B.untilC.whenD.after4.It is almost five years _ we saw each other last time.A.before B.since C.after D.because 连接词连接词before的小结：的小结：1.We had sailed four days and four nights before we saw land.2.We hadnt run a mil
18、e before he felt tired.3.Please write it down before you forget it.4.Before I could get in a word,he had measured me.Before从句中谓语不用否定式。如：从句中谓语不用否定式。如：Before they reached the station,the train had gone.1)句型句型It will be/was段时间段时间before“还要过多久才还要过多久才”It will be two years before he leaves the country.2)句型
19、句型It will be/was not段时间段时间before“不多久就不多久就”It wasnt two years before he left the country.3)句型句型It is段时间段时间since时间的计算一律从时间的计算一律从since从句的从句的 动作完成或状态结束时算起。动作完成或状态结束时算起。It is three years since she was in the army.It is three years since she joined the army.1)Apply it after wetting your hair with warm wat
20、er.You apply it after you wet your hair with warm water2)After shampooing,squeeze out the extra water and apply conditioner.After you shampoo,you squeeze out the extra water and apply conditioner3)After washing out the shampoo,apply the conditionerand comb it into your hair.After you wash out the sh
21、ampoo,you apply the conditionerand comb it into your hair.4)Before they were shown around it,the visitors watched a video about the museum.Before being shown around it,the visitors watched a video about the museum.before/after doing/being done5.since-自从自从,通常通常主句主句用现在完成时用现在完成时I have never been there
22、again since I graduated from the university.The captain has traveled almost everywhere in the world since he became a pilot.It is just a week since we arrived here.-Have you known Mr.Smith for a long time?-Yes,since he _ our Badminton Club.A.has joined B.joins C.had joined D.joined1)I have known him
23、 ever since he was a boy.2)He had worked here since he had graduated from the university.3)It is(has been)two years since he came here.4)It was(had been)two years since he had come here.6.no sooner than-一一就就 He had no sooner fallen asleep than he heard a knock on the door.(no sooner than 用于句首要求倒装用于句
24、首要求倒装)No sooner had he fallen asleep than he heard a knock on the door.Hardly when Scarcely when 他刚离开家，天就开始下雨了。他刚离开家，天就开始下雨了。(Hardly)Hardly had he left home when it began to rain.7.as soon as-Did you remember to give Mary the money you owed her?-Yes,I gave her the moment I saw her.一些词，如一些词，如the mome
25、nt,the minute,the instant,immediately,directly,instantly,hardlywhen,scarcelywhen,no soonerthan等也可引导一个时等也可引导一个时 间状间状语从句，相当于语从句，相当于as soon as的意思。的意思。I didnt wait a moment,but came immediately you called.一些含有一些含有time的名词短语，如的名词短语，如every time,each time,next time,by the time,the first time等，以及等，以及the day,
26、the year,the morning等，也可引导一个时间状语从句。等，也可引导一个时间状语从句。The day he returned home,his father was already dead.Next time you come,please bring your composition.8.The first time等等 I thought her nice and honest _ I met her.A.first time B.for the first time C.the first time D.by the first time Unit 4 Grammar(2
27、)Adverbial Clauses of Reason原因状语从句原因状语从句because,as,since,now that,和和considering that,seeing that 这六这六个连词都用于表示表示原因个连词都用于表示表示原因,但在语气但在语气上一个比一个弱上一个比一个弱.I came back late yesterday because I was on duty.Since everyone is here,lets begin our meeting.As he didnt know much English,he looked up the word in t
28、he dictionary.He must be ill,for he is absent from the meeting.1.由于准备充分，他在面试中一点也不紧张。由于准备充分，他在面试中一点也不紧张。(not at all)Because he was well-prepared,he didnt feel nervous at all during the interview.2._ youve got a chance,you might as well make full use of it.A.Now that B.After C.Although D.As soon as 3.
29、_ everybody knows about it,I dont want to talk about it any more.A.For B.Even C.Since D.However4.Did he come _ he wanted help?A.since B.as C.because D.now that1.It was _ it was too expensive that I didnt buy it.A.since B.as C.because D.now that2.He got the highest marks in the final exam.It was all
30、_ he had worked very hard.A.why B.that C.whether D.because 3.It rained last night,_ the ground is wet this morning.A.since B.as C.because D.for4._ a difficult situation,so you should send him a message and give him some advice.A.As he is in B.He is in C.Being in D.He being in 1.今天下午我没空，我和牙医有约。今天下午我没
31、空，我和牙医有约。(appointment)I am not free this afternoon because I have an appointment with my dentist.2.我不需要买新车，我的那辆旧车还很好。我不需要买新车，我的那辆旧车还很好。I dont need to buy a new car,because my old one is still in good condition.1.How can you expect to learn anything when you never listen?2.How can you hope for mercy when you show none?3.He paid for a seat when he could have entered free.4.We live in an age when many things are done on the computer.5.The time is not far away when China can send a manned spaceship to the moon.
