句子状语从句

1、状语从句考点状语从句考点 1 1、各种从属连词的含义及用法比较；、各种从属连词的含义及用法比较；2 2、no matter wh- no matter wh- 与与 wh-ever wh-ever 引导的从句引导的从句的区别；的区别；3 3、状语从句的时态问题；、状语从句的时态问题；4 4、状语从句的倒装问题；、状语从句的倒装问题；5 5、状语从句与其它从句的区别。、状语从句与其它从句的区别。1、时间状语从句、时间状语从句问题问题1： Dont be afraid of asking for help it is needed. （03全国卷）全国卷） Aunless BsinceCaltho

2、ugh Dwhen根据句意，此处只能为时间状语从句，故答案为根据句意，此处只能为时间状语从句，故答案为D。unless 引导条件状语从句，意为引导条件状语从句，意为“除非除非”；although 引导让步状引导让步状语从句，意为语从句，意为“虽然虽然”；since 虽引导时间状语从句，但意思为虽引导时间状语从句，但意思为“从从以来以来”，这些都与题意无关。引导时间状语的引导词很，这些都与题意无关。引导时间状语的引导词很多，多，复习复习when 时要注意比较它与时要注意比较它与while 与与 as 的区别的区别。D Dwhen, while, as 三者的具体用法关键在于动作发生的三者的具体用

3、法关键在于动作发生的时间及从句的动词。时间及从句的动词。while 表时间，从句需用延续性动词，表时间，从句需用延续性动词，不用瞬间动词；不用瞬间动词；when 表时间，从句既可用延续性动词，表时间，从句既可用延续性动词，又可以用瞬间动词；又可以用瞬间动词；as 表时间，与表时间，与when 相似，但侧重相似，但侧重强调主、从句动作同点或同段进行，可用延续行动词的一强调主、从句动作同点或同段进行，可用延续行动词的一般过去式表式过去进行时。般过去式表式过去进行时。when, while 后还可以接分词后还可以接分词短语。短语。when 作并列连词，表示一个动作在发生时，另一作并列连词，表示一个动

4、作在发生时，另一个动作接着发生，这时就不能用个动作接着发生，这时就不能用while、as。 I was walking on the street when suddenly someone patted me on the shoulder. while 作并列连词，表示两种情况对比。作并列连词，表示两种情况对比。 He was playing the guitar while his sister was watching TV. 问题问题2：1) Was his father very strict with him when he was at school? Yes. He had

5、never praised him he became one of the top students in his grade. （03北京春季）北京春季） AafterBunlessCuntilDWhen2) Simon thought his computer was broken _ his little brother pointed out that he had forgotten to turn it on. （05北京春季）北京春季） A. until B. unless C. after D. because C CA A until / till “直到直到止止”(肯定句

6、，主句是延续性动词肯定句，主句是延续性动词); notuntil “直到直到才才”(否定句，主句是终止性动词否定句，主句是终止性动词); until 可用于倒装句和强调句，可用于倒装句和强调句，till不用于句首。不用于句首。 Not until I returned did she finish her homework. It was not until I returned home that she finished her homework.问题问题3：1、The American Civil War lasted four years _ the North won in the

7、end. (05广东卷广东卷) A. after B. before C. when D. then2、He made a mistake, but then he corrected the situation _ it got worse. （03北京）北京） A. until B. when C. before D. as B Bbefore 从句是高考中的一大热点，从时间概念上不难作出从句是高考中的一大热点，从时间概念上不难作出判断。注意它的翻译：在肯定句中一般翻译成判断。注意它的翻译：在肯定句中一般翻译成“（主句（主句的动作）的动作）才才（从句的动作）（从句的动作）”，如题，如题1；

8、或；或“还没有还没有（从句的动作）（从句的动作）就就（主句的动作）（主句的动作）”，如题，如题2。C C问题问题4： Did you remember to give Mary the money you owed her? Yes, I gave it to her _ I saw her. （01北京春季） Awhile Bthe moment Csuddenly DonceB Bthe time（当（当的时刻）的时刻）, the moment / minute / second / instant (一一 就就 ), next time (下次下次), the first time(第一

9、次第一次的时候的时候), the last time (上次上次的时候的时候)，immediately（一（一就就）, instantly（一（一就就）, directly（一（一就就）等词或）等词或词组可引导表示时间的状语从句；还有一些表示习惯性动作词组可引导表示时间的状语从句；还有一些表示习惯性动作的词如：的词如：every time（每次）（每次）, each time（每次）（每次）, whenever（每当）等也可引导表示时间的状语从句。（每当）等也可引导表示时间的状语从句。 2、条件状语从句、条件状语从句问题问题1：1、The WTO cannot live up to its n

10、ame _ it does not include a country that is home to one fifth of mankind. （2000全国）Aas long as BwhileCif Deven though2、 It is known to all that _ you exercise regularly, you wont keep good health. （05重庆卷） A. unless B. whenever C. although D. if C CA A unless 相当于 if not，意思是“除非”“如果不就”。这也是高考的热点之一。复习时也应给

11、予高度重视。问题问题2：1、_ I can see, there is only one possible way to keep away from the danger. （04北京春季）北京春季） A. As long as B. As far as C. Just as D. Even if 2、I always take something to read when I go to the doctors _ I have to wait. （05全国卷全国卷3） Ain case Bso that Cin orderDas if B BA A as long as 与 as far

12、 as 都可引导条件状语从句，as long as 表示“只要”，as far as 表示“就而论（而言）”。题1根据题意应该选用B。in case 表示“以防”，根据题2的句意，不难作出选择。3、让步状语从句、让步状语从句问题问题1： 1、 _ I accept that he is not perfect, I do actually like the person. （04江苏） A. While B. Since C. Before D. Unless2、Allow children the space to voice their opinions, _they are differ

13、ent from your own. (05湖南卷）(B) A. untilB. even ifC. unless D. as though A AB B while 是高考中的高频词，它既可引导时间状语从句，又可引导并列句，还可引导让步状语从句，表示“尽管”。even if 等于 even though，表示“即使、尽管”。as though 等于 as if，引导方式状语从句，表示“好像、似乎”。问题问题2： 1、 He tried his best to solve the problem, _ difficult it was. （05天津卷） A. however B. no mat

14、ter C. whatever D although 2、The old tower must be saved, _the cost. （05浙江） Ahowever Bwhatever Cwhichever Dwherever A AB Bno matter wh- 与与 wh-ever 的联系及区别：的联系及区别：no matter wh- 只引导让步状语从句，此时与 wh-ever通用。如: No matter when / Whenever he comes back, he should be invited to the party.wh-ever又可引导名词性从句， No ma

15、tter wh-不能。如：Whatever I can do for you will be nothing but paying a debt. Whoever can help us will be welcome 4. 状语从句的时态问题状语从句的时态问题问题问题1：1、The house could fall down soon if no one_ some quick repair work. （04全国IV） A has done B is doingC does D had done 2、It is almost five years _ we saw each other l

16、ast time. （05北京春季）A. before B. since C. after D. when 在条件，时间和让步从句中，用一般现在时表示一般将来时，用现在完成时表将来完成时，用一般过去时表过去将来时。在 since 引导的时间状语从句中，动词一般都用一般过去时，而主句常用现在完成时。C CB B5、状语从句的倒装问题、状语从句的倒装问题问题问题1：1、So difficult _ it to live in an English-speaking country that I determined to learn English. (01 上海) A. I have felt

17、B. have I felt C. I did feel D. did I feel2、Not until all the fish died in the river, _ how serious the pollution was. (95 NMET) A. did the villagers realize B. the villagers realized C. the villagers did realize D. didnt the villagers realize 状语从句的倒装一般有下面几种情况： 否定词开头； so 加 adj. 开头； as / though引导的让步状

18、语从句。D DA A特别注意：特别注意： Hardly when No sooner than Child as he is, Hardly had he got to the station, the train left. No sooner had he got to the station, the train left. Child as he is, he can speak seven foreign languages. 6、状语从句与并列句的区别、状语从句与并列句的区别问题问题1：1、Though he is in his sixties, _ he works as har

19、d as a young man A. yet B. but C. and D. and yet2、 Excuse me for breaking in, _ I have some news for you. (NMET02)A. so B. and C. but D. yet 题1是主从复合句，所以中间不能使用并列连词 and; or; but; so 等。yet 是副词，只有 yet 可以与 though 连用。题2为并列句，而“Excuse , but ”为一固定搭配。在复习中需要细心的分析句子结构和成分。A AC C Revision ofthe Adverbial Clauses状

20、语从句复习状语从句复习九种常用的状语从句及其常用的连接词九种常用的状语从句及其常用的连接词 时间状语从句时间状语从句地点状语从句地点状语从句原因状语从句原因状语从句条件状语从句条件状语从句让步状语从句让步状语从句结果状语从句结果状语从句目的状语从句目的状语从句方式状语从句方式状语从句比较状语从句比较状语从句 九种常用的状语从句及其常用的连接词九种常用的状语从句及其常用的连接词 时间状语从句时间状语从句 when, while, as, before, after, as soon as, till, until, notuntil, the first/second/last time, th

21、e moment, the minute, the instant, immediately, directly, instantly, hardlywhen, scarcelywhen, no soonerthan where, wherever because, since, as, now that, seeing that, considering that if, unless, now (that), as(so) long as, in case, on condition that, suppose/supposing, provided/providing 地点状语从句地点状

22、语从句原因状语从句原因状语从句条件状语从句条件状语从句九种常用的状语从句及其常用的连接词九种常用的状语从句及其常用的连接词 结果状语从句结果状语从句so that, sothat, suchthat so that, in case, for fear that, how, as, as if/as though than, asas, not so/asas, the +比较级比较级, the +比较级比较级 目的状语从句目的状语从句方式状语从句方式状语从句比较状语从句比较状语从句让步状语从句让步状语从句 although, though, even though/if, as, while

23、, no matter which/what/when/where/who/how, whichever, wherever, whatever, whoever, whenever, however, whetheror； 九种常用的状语从句九种常用的状语从句 时间状语从句时间状语从句地点状语从句地点状语从句原因状语从句原因状语从句条件状语从句条件状语从句让步状语从句让步状语从句结果状语从句结果状语从句目的状语从句目的状语从句方式状语从句方式状语从句比较状语从句比较状语从句 状语从句有九种，状语从句有九种， 时地原因条状补，时地原因条状补，目比结果方让步，目比结果方让步，连词引导各不同；连词

24、引导各不同；主句通常前面走，主句通常前面走， 连词引导紧随后，连词引导紧随后，从句若在主前头，从句若在主前头， 主从之间有个逗。主从之间有个逗。 While I was wondering at this, our schoolmaster took his place. ( )2. Where there is a will, there is a way. ( )3. Now that/Since everybody is here, lets begin our meeting. （ ）4. Ill speak slowly so that you can understand me.

25、( )时间时间地点地点原因原因目的目的5. So clever was he a student that he was able to work out all the difficult problems. ( )6. As long as you dont lose heart, youll succeed. ( )7. Try as he might, he could not find a job. ( )8. The old lady treats the boy as if he were his own son. ( ) 结果结果条件条件让步让步方式方式1、各种从属连词的含义及

26、用法、各种从属连词的含义及用法 比较；比较；2、no matter wh- 与与 wh-ever 引引 导的从句的区别；导的从句的区别；3、状语从句的时态问题；、状语从句的时态问题；4、状语从句倒装及紧缩问题；、状语从句倒装及紧缩问题；5、状语从句与其它从句的区别。、状语从句与其它从句的区别。考点考点难难点点1. 时间状语从句时间状语从句问题问题1:1. (04北京春北京春) We were swimming in the lake _ suddenly the storm started. A. when B. while C. until D. before2. (02上海上海) He w

27、as about to tell me the secret _ someone patted him on the shoulder. A. as B. until C. whileD. when3. (05上海上海) He transplanted the little tree to the garden _ it was the best time for it. A. where B. when C. thatD. until4. (05福建福建) Did Jack come back early last night? Yes. It was not yet eight ocloc

28、k _ he arrived home. A. Before B. when C. thatD. until5. (06辽宁辽宁) He was about halfway through his meal _ a familiar voice came to his ears. A. why B. where C. when D. whileA AD DB BB BC C连接词连接词when的用法小结的用法小结1. when引导的时间状语从句的谓语动词可以是可延续引导的时间状语从句的谓语动词可以是可延续 的，也可以是表短暂性动作的动词，可用于主句和从句的，也可以是表短暂性动作的动词，可用于主

29、句和从句 动作同时发生或从句动作先于主句动作。如：动作同时发生或从句动作先于主句动作。如： When the film ended, the people went back. When I lived there, I used to go to the seashore on Sundays.2. 可用作并列连词，其意义为可用作并列连词，其意义为“那时，这时那时，这时”，相当于，相当于 and at this/that time。常用于下列句式：。常用于下列句式： Somebody was doing something/was about to do sth./was on the po

30、int of doing sth. when (刚要刚要这时突然这时突然)3. 还可以表示原因还可以表示原因“既然既然”，相当于，相当于since; considering that。如：。如： It was foolish of you to take a taxi when you could easily walk there in five minutes .问题问题2:6. (06天津天津) The cost of living in Glasgow is among the lowest in Britain, _ the quality of life is probably o

31、ne of the highest. A. since B. when C. as D. while7. (04年江苏年江苏) _ I accept that he is not perfect, I do actually like the person. A. While B. Since C. Before D. Unless连接词连接词while的用法小结的用法小结 1. while引导的动作必须是持续性的，侧重主句动作和从引导的动作必须是持续性的，侧重主句动作和从句动作相对比。如：句动作相对比。如： Please dont talk so loud while others are

32、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。D DA A连接词连接词when, while, as的用法区别：的用法区别：1while引导的时间状语从句的谓语动词必须是可延续的，引导的时间状语从句的谓语动词必须是可延续的， 而而when引导的时间状语从句的谓语动词是可延续的，也引导的时间状语从句的谓语动词是可延续的，也 可以是表短暂性动作的动词。如：可以是表短暂性动作的动词。如：When/While he was eating his breakfast,

33、he heard the doorbell ring. When I stopped my car, a man came up to me. (不可用不可用 while)2从句动作发生在主句动作之前时，只能用从句动作发生在主句动作之前时，只能用when引导这个引导这个 从句，不可用从句，不可用as或或while。如：。如： When you have finished your work, you may have a rest.3表示表示“随着随着”，连词用，连词用as，不用，不用when或或while。如：。如： As the election approached, the viole

34、nce got worse.4如果主句表示的是短暂动作，而从句用延续性动作的进行如果主句表示的是短暂动作，而从句用延续性动作的进行 时态表示在一段时间内正在进行的动作时，时态表示在一段时间内正在进行的动作时，when, while 与与as 可互换使用。如：可互换使用。如： When/While/As I was walking down the street, I came across an old friend of mine.问题问题3:1. (01北京春北京春)Did you remember to give Mary the money you owed her? Yes. I g

35、ave it to her _ I saw her. A. whileB. the moment C. suddenlyD. once2. (1998上海上海) I thought her nice and honest _ I met her. A. first time B. for the first time C. the first timeD. by the first time3. _ entered the office when he realized that he had forgotten his report. A. He hardly had B. Had he h

36、ardly C. Hardly had heD. Hardly he had B BC CC C小结：小结：1一些词，如一些词，如the moment, 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 间状语从句，相当于间状语从句，相当于as soon as的意思。的意思。 I didnt wait a moment, but came immediately you called.2一些含有一些含有time的名词

37、短语，如的名词短语，如every time, each time, next time, by the time等，以及等，以及the day, 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.3. 如果如果hardly或或no sooner或或scarcely置于句首，句子必置于句首，句子必 须用部分倒装结构。须用部分倒装结构。

38、Hardly had I got home when it began to rain.问题问题4:1. (03北京春北京春) 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. when2. (03上海上海) A good storyteller must be able to hold listeners

39、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; thenC CD DB B小结：小结：till, until和和notuntil：1.until/till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

40、句用于肯定句时，主句的动词 是延续性动词，表示动作或状态一直持续到是延续性动词，表示动作或状态一直持续到until/till所所 表示的时间，意为表示的时间，意为“某动作一直延续到某时间点才停某动作一直延续到某时间点才停 止止”。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，意为为肯定，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： He wont go to bed till/until she returns.3till不可以置于句首，而不可以置于句首，

41、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.问题问题5:1. (03年北京年北京) He made a mistake, but then he corrected the situation _ it got worse. A. until B. when

42、 C. beforeD. as2. (04福建福建) 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. (06四川四川)Why didnt you tell him about the meeting? He rushed out of the room_I could say a word. A. before B. untilC. whenD. after4. (0

43、5北京春北京春) It is almost five years _ we saw each other last time. A. before B. since C. after D. because C CC CA AB B连接词连接词before的小结：的小结：一、含义一、含义1 We had sailed four days and four nights before we saw land.2 We hadnt run a mile before he felt tired.3 Please write it down before you forget it.4Before I

44、 could get in a word, he had measured me. “才才” “不到不到就就” “趁趁” “还没来得及还没来得及” 二二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. 三三1）句型）句型It will be/was段时间段时间before“还要过还要过多久才多久才” 如：如：It will be two years before he leaves the country. 2）句型）句型It will be/was not一段时间一段时间

45、before“不不多久就多久就” 如：如： 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。如：动作完成或状态结束时算起。如： It is three years since she was in the army. It is three years since she joined the army. 2、条件状语从句、条件状语从句问题问题1：1、The WTO cannot live up to its name _

46、 it does not include a country that is home to one fifth of mankind. （2000全国）全国）Aas long as BwhileCif Deven though2、 It is known to all that _ you exercise regularly, you wont keep good health. （05重庆卷）重庆卷） A. unless B. whenever C. although D. if C CA A unless 相当于相当于 if not，意思是，意思是“除非除非”“如果不如果不就就”。这也

47、是高。这也是高考的热点之一。复习时也应给予高度重视。考的热点之一。复习时也应给予高度重视。问题问题2：1、_ I can see, there is only one possible way to keep away from the danger. （04北京春季）北京春季） A. As long as B. As far as C. Just as D. Even if 2、I always take something to read when I go to the doctors _ I have to wait. （05全国卷全国卷3） Ain case Bso that Cin

48、 orderDas if B BA A as long as 与与 as far as 都可引导条件状语从句，都可引导条件状语从句，as long as 表示表示“只要只要”，as far as 表示表示“就就而论（而言）而论（而言）”。题题1根据题意应该选用根据题意应该选用B。in case 表示表示“以防以防”，根据题，根据题2的句意，不难作出选择。的句意，不难作出选择。3、让步状语从句、让步状语从句问题问题1： 1、 _ I accept that he is not perfect, I do actually like the person. （04江苏）江苏） A. While B

49、. Since C. Before D. Unless2、Allow children the space to voice their opinions, _they are different from your own. (05湖南卷）湖南卷） A. untilB. even ifC. unless D. as though A AB B while 是高考中的高频词，它既可引导时间状语从句，是高考中的高频词，它既可引导时间状语从句，又可引导并列句，还可引导让步状语从句，表示又可引导并列句，还可引导让步状语从句，表示“尽尽管管”。even if 等于等于 even though，表示，表

50、示“即使、尽管即使、尽管”。as though 等于等于 as if，引导方式状语从句，表示，引导方式状语从句，表示“好像、好像、似乎似乎”。问题问题2： 1、 He tried his best to solve the problem, _ difficult it was. （05天津卷） A. however B. no matter C. whatever D although 2、The old tower must be saved, _the cost. （05浙江） Ahowever Bwhatever Cwhichever Dwherever A AB Bno matter

51、 wh- 与与 wh-ever 的联系及区别：的联系及区别：no matter wh- 只引导让步状语从句，此时与只引导让步状语从句，此时与 wh-ever通用。通用。如如: No matter when / Whenever he comes back, he should be invited to the party.wh-ever又可引导名词性从句，又可引导名词性从句， No matter wh-不能。如：不能。如：Whatever I can do for you will be nothing but paying a debt. Whoever can help us will

52、be welcome.4. 状语从句的时态问题状语从句的时态问题问题问题1：1、The house could fall down soon if no one_ some quick repair work. （04全国全国IV） A has done B is doing C does D had done 2、It is almost five years _ we saw each other last time. （05北京春季）北京春季）A. before B. since C. after D. when 在条件，时间和让步从句中，用一般现在时表示一般将在条件，时间和让步从句中，

53、用一般现在时表示一般将来时，用现在完成时表将来完成时，用一般过去时表过去将来时，用现在完成时表将来完成时，用一般过去时表过去将来时。在来时。在 since 引导的时间状语从句中，动词一般都用一般引导的时间状语从句中，动词一般都用一般过去时，而主句常用现在完成时。过去时，而主句常用现在完成时。C CB B5、状语从句的倒装问题、状语从句的倒装问题问题问题1：1、So difficult _ it to live in an English-speaking country that I determined to learn English. (01 上海上海) A. I have felt B

54、. have I felt C. I did feel D. did I feel2、Not until all the fish died in the river _ how serious the pollution was. (95 NMET) A. did the villagers realize B. the villagers realized C. the villagers did realize D. didnt the villagers realize 状语从句的倒装一般有下面几种情况：状语从句的倒装一般有下面几种情况： 否定词开头；否定词开头； so 加加 adj.

55、 开头；开头； as / though引导的让步状语从句。引导的让步状语从句。D DA A特别注意：特别注意： Hardly when No sooner than Child as he is, Hardly had he got to the station when the train left. No sooner had he got to the station than the train left. Child as he is, he can speak seven foreign languages. 6、状语从句与并列句的区别、状语从句与并列句的区别问题问题1：1、Tho

56、ugh he is in his sixties, _ he works as hard as a young man A. yet B. but C. and D. and yet2、 Excuse me for breaking in, _ I have some news for you. (NMET02) A. so B. and C. but D. yet 题题1是主从复合句，所以中间不能使用并列连词是主从复合句，所以中间不能使用并列连词 and; or; but; so 等。等。yet 是副词，只有是副词，只有 yet 可以与可以与 though 连用。题连用。题2为为并列句，而并

57、列句，而“Excuse , but ”为一固定搭配。在复习中需为一固定搭配。在复习中需要细心的分析句子结构和成分。要细心的分析句子结构和成分。A AC C _ he heard this, he got very angry. 2. I met Lucy_ I was walking along the river.3. _ a child, he lived in the countryside. A. when B. while C. as对比训练对比训练 1 1A AB BC C1. We were about to leave_ it began to rain.2. She thou

58、ght I was talking about her son, _, in fact, I was talking about my son.3. Hardly had I finished my composition _ the bell rang. A. when B. while C. as D. during对比训练对比训练 2 2 A AB BA A1. Child _ she is, she know a lot.2. He did the experient _ he was told.3. The pianos in the other shop will be cheap

59、er, but not _ good. A. during B. as C. so D. though E. both B and C 对比训练对比训练 3 3 E EB BB B1. He would have a look at the bookstores _ he went to town.2. We decide to finish the work on time, _ happens.3. If we work with a strong will, we overcome any difficulty, _ great it is.4. Ill give the book to

60、 _ likes English. A. whenever B. whoever C. whatever D. however对比训练对比训练 4 4 A AC CD DB B对比训练对比训练 5 5 1. It will be years _ we meet again.2. It is ten years _ I came to this town.3. It is ten years ago _ I came to this town. A. when B. that C. before D. sinceC CD DB B对比训练对比训练 6 6 D DB BA A1. _ it rai