四级语法讲座3：从句.ppt

1、重点三 定 语 从 句,从 句 (重点三 定 语 从 句),I. 考点分析定语从句主要考点是关系代词，尤其是that, as, 介词+which的用法。 II知识点定语从句也称形容词性从句，在整个句子中起定语的作用。定语从句通常置于它所修饰的名词和代词之后，这种名词和代词被称为先行词。 引导定语从句的关联词为关系代词和关系副词。其中，关系代词有who, whom, whose, that, which等，在从句中可作主语、宾语，定语等；关系副词有when, where, why等词，在定语从句中只用作状语。其中：,1. who, whom, whose指人，在从句中分别作主语（在非正式英语中也

2、可作宾语,但可省略）、宾语和定语；whose也可指物，作定语；that可指人，也可指物，在从句中可作主语，也可作宾语；which指物，在从句中可作主语，也可作宾语。注意：whom, that, which在从句中作宾语时可以省略。例句:,1）The man who was here yesterday is a painter. 2) The man (who) I saw is called Smith. 3) I know the man (whom) you mean. 4) A child whose parents are dead is called an orphan. 5) I

3、d like a room whose window looks out over the sea. 6) A letter that is written in pencil is hard to read. 7) The letter (that) I received from him yesterday is very important. 8) Is he the man that sells eggs? 9) That is the boy (that) you are looking for.,2. When 指时间，where指地点，why指原因，在从句中都作状语。例如： 1)

4、 We will put off the picnic until next week when the weather may be better. 2) He has reached the point where a change is needed. 3) That is no reason why you should leave.,定语从句可分为限定性定语从句和非限定性定语从句两种。限定性定语从句一般紧跟在先行词的后面修饰、限定先行词，它与先行词之间没有逗号，去掉后会影响全句意思的完整性。非限定性定语从句用来解释、说明先行词或主句所指内容，与先行词之间用逗号隔开。 1) I lik

5、e to chat with John, who is a clever fellow. 2) Water, which is a clear liquid, has many uses.,III定语从句中的四级考点:,1.在下列情形下只能用that，而不能用which。 1)序数词或最高级形容词修饰先行词时： a. The first English novel that I read was the Tale of Two Cities by Charles Dickens. b. Tom is the most diligent students that I have ever kno

6、wn. 2) 先行词是不定代词或被All, everything, nothing anything, something等不定代词修饰先行词时： a. Mr. Green had told us something that we should do in the summer vocation. b. I heard all that she told to her mother.,2. that, which 和as,非限定性定语从句中的先行词在从句中作主语指人、指物或主句所指代的一个意义时，引导词不能用that，而只能用which或 as。而后两者的区别是which引导的非限定性定语从

7、句可放在句中和句末，却不能置于句首，as引导的从句既可放在句中、句末，也可置于句首。 a. He once helped a woman, which(as) was reported in the newspaper. The dog, which(as) is black, is running toward the strange man. b. As is known, the director of the company is going to come to our branch to have a inspection of the production here.,3. wh

8、ich和whom在从句中作介词的宾语,which和whom在从句中作介词的宾语时，介词一般放在二者之前，也可放在从句原来的位置上，在含有介词的固定词组中介词只能放在原来的位置上，而不能放在二者之前。 a. Please tell me from whom you borrowed the English novel. Please tell me whom you borrow the English novel from. b. The house in which he lived before now becomes a restaurant. The house which he li

9、ved in before now becomes a restaurant. c. This is the magazine (that) you are looking for.,4. 介词which的结构可代替定语从句中的引导词when和where。 a. He was born in Germany where(in which) he stayed for 12 years. b. She arrived at 12 oclock when(at which) it was raining hard. 5.but, than也可作关系代词。 a. You spent more mon

10、ey than was intended to be spent. b. There are very few but admire his talents.（很少有人不赞赏他的才干的。but = who dont） 从历年四级词汇语法考点中分析可知，定语从句出现的频率很高，主要集中在以上所讲的定语从句的特殊用法中，因此需重点掌握这些。,四级真题 定语从句,1. Helen was much kinder to her youngest child than she was to the others,_, of course, made others jealous. (93/06/59)

11、A) who B) that C) what D) which D) 题意：海伦对她最小的孩子要比别的孩子好得多，这当然让其他孩子嫉妒了。 解析：本题中which是关系代词，引导一个非限定性定语从句，指代前面整句话的意思。 2._ is known to the world, Mark Twain is a great American writer. (93/06/67) A)That B) Which C) As D) It C) 题意：全世界的人都知道马克?吐温是一位伟大的美国作家。 解析：As和which都可引导非限定定语从句，which从句只可放在句中和句末，而as引导的从句可放在句

12、中、句末和句首，故此处只能选as。,3. The residents, _ had been damaged by the flood, were given help by the Red Cross. (93/6/68) A) all their homes B) all whose homes C) all of whose homes D) all of their homes C) 题意：红十字会给那些居民提供帮助，他们的房子在洪水中被毁。 解析：据题意和句子结构判断中间逗号隔开的部分应为非限定性定语从句，用来解释说明前面的residents，此处所填的先行词用来指代前面的resid

13、ents。它与homes之间的关系是一种所属关系，故用代词whose。故C正确。 4. Language is a city, to the building of _ every human being brought a stone. (94/01/51) A)which B) that C) it D) this A) 题意：语言是一座城市，每一个人都为它的建设增砖添瓦。 解析：根据句子结构和句义，空格处应为一个引导定语从句的关系代词用来指代先行词a city。又由于是非限定性定语从句，故只能选A。,5. You will want two trees about ten feet ap

14、art, from _ to suspend your tent. (95/06/50) A) there B) them C) which D) where C) 题意：你需要两棵相距十英尺远的树，在树上可悬挂你的帐篷。 解析：此句逗号后的部分用来修饰说明前面的two trees，是个非限定性定语从句，又由于from为介词，故只能选C。由于从句和主句的主语一致，故从句中省略了主语和谓语动词you want。这种形式又可被看作介词+ which +动词不定式短语的结构。若无from，此处可选D。 6. _ might be expected, the response to the quest

15、ion was very mixed. (96/6/27) A)As B) That C) It D) What A) 题意：这个问题的答案极为复杂，这一点人们可能已经预见到了。 解析：同题2。,7. It is useful to be able to predict the extent _ which a price change will affect supply and demand. (97/01/29) A)from B) with C) to D) for C) 题意：能够预测价格变化将影响供需的程度是有益的。 解析：本题的测试点是介词的用法和介词+which/whom引导的

16、定语从句。引导定语从句的关系代词除了做从句中动词的宾语外，还可做介词的宾语，这些介词常有：with 表伴随状态；of表部分与整体的关系；to表方向、目的；for表示对象；from表示来源。从本题可看出答案应与动词连用，指明预测的方向；且toextent为固定介词短语，表到的程度。 8. Living in the central Australian desert has its problems, _obtaining water is not the least. (98/01/42) C) 题意：居住在澳大利亚中部的沙漠地区有许多问题，取水就是个不小的的问题。 解析：本题的测试点是介词的

17、用法和介词+which/whom引导的定语从句。Lest做介词表示对介词of的选择，of 和which指代的先行词problems是所属关系。,9. The British are not so familiar with different cultures and other ways of doing things, _ is often the case in other countries. (98/06/58) A) as B) what C) so D) that A) 题意：英国人不太熟悉异文化和做事的其他方式，这也是其他国家常有的事。 解析：此句中只有as可引导非限定性从句。

18、 10. We need a chairman _.（98/06/62） A) for whom everyone has confidence B) in whom everyone has confidence C) who everyone has confidence of D) whom everyone has confidence on B) 题意：我们需要一个人人都信任的主席。 解析：此句中have confidence in（对有信心/信任感）为固定短语，介词提前、先行词指人时只能为in whom。即介词+whom引导的限定性定语从句。,11. The course norm

19、ally attracts 20 students per year, _ up to half will be from overseas. (98/06/70) A) in which B) for which C) with which D) of whom D) 题意：这门课程通常每年招收20名学生，其中多大半数的学生来自海外。 解析：本题的测试点是介词的用法和介词+which/whom引导的定语从句。Up to half和whom指代的先行词students之间是所属关系，故应为of whom。 12. A survey was carried out on the death ra

20、te of new-born babies in that region, _ were surprising. (99/01/42) A) as results B) which results C) the results of it D) the results of which D) 题意：那一地区新生儿死亡率的调查结果令人吃惊。 解析：同题10。,13. He came back late, _ which time all the guests have already left. (99/06/41) A) at B) after C) by D) during C) 题意：他回

21、来很晚，回来时所有的客人都已经走了。 解析：本题的测试点是介词的用法和介词+which/whom引导的定语从句。由从句的现在完成时时态可判断此处的时间引导词应为by。 14. I hope all the precautions against air pollution _ suggested by local government will be seriously considered here. (99/06/53) A) as B) while C) after D) since A) 题意：我希望当地政府将严肃考虑提出预防这儿空气污染的所有措施。 解析：此句为省略从句助动词are的

22、非限定性定语从句。,15. Ive never been to Beijing, but it is the place _. (99/06/55) A) that I want to visit it most B) where Id like to visit C) in which Id like to visit D) I most want to visit D) 题意：我从未去过北京，但它是我最想参观的地方。 解析：此句的先行词虽为指地点的place，但定语从句中缺宾语，且visit是及物动词，故只能选A。 16. Beer is the most popular drinks a

23、mong drinkers,_ overall consumption is significant.(00/06/32) A) whose B) which C) that D) what A) 题意：啤酒是饮酒者最喜爱的饮品。 解析：此句从句的主语和先行词间的关系属从属关系，故选A。,17. The professor could hardly find sufficient grounds _ his arguments in favor of the new theory. (00/06/36) A) to be based on B) to base on C) which to b

24、ase on D) on which to base D) 题意：教授难以找到充足的论据来证明他赞成新理论的论点。 解析：此句中的先行词在从句中作base on的宾语,此处考察的是名词+介词+which/whom+动词不定式结构的定语从句。 18. Living in the western part of the country has its problem, _ obtaining fresh water is not the least. (00/06/46) A) with which B) for which C) of which D) which C) 题意：生活在该国家的西部

25、地区有其自身的问题，获取饮用水就是一个难题。 解析：非限定性定语从句与其修饰的先行词之间是从属关系，故选C。,19. The hours _ the children spend in their one-way relationship with television people undoubtedly affect their relationship with real-life people. (01/1/54) A) when B) on which C) that D) in which C) 题意：孩子们与电视人物之间的关系是单向的，他们花在这种关系上的时间无疑会影响他们与现实

26、生活中人们间的关系。 解析：从句中缺直接宾语，故选C。 20. Agriculture was a step in human progress _ which subsequently there was not anything comparable until our own machine age. (01/01/64) A) to B) in C) for D) from A) 题意：农业是人类发展进程中的一步，在我们的机器时代到来之前，任何事物都不能和它相提并论。 解析：先行词作定语从句中短语be comparable to(把比作)的宾语，故此处应为to which。,21. G

27、overnment reports examination compositions legal documents and most letters are the main situations _ formal language is used. (01/06/46) A)in which B) on which C) in that D) at what A) 题意：正式用语主要用于政府报告、考试作文、法律文件和商业信函。 解析：先行词在定语从句中作地点状语，而in the situation（在该条件下）为固定介词短语，故A正确。 22.The residents, _ had be

28、en damaged by the fire, were given help by the Red Cross. (02/6/64) A) all of their homes B) all their homes C) whose all homes D) all of whose homes D) 题意：那些家庭被大火彻底毁掉的人们受到了红十字会的救助。 解析：问题所在的部分是一个定语从句，显然必须有关系代词，表示所属关系的代词是whose，因此答案应为C）或D）。而在表示他们所有的家，正常的说法是all their homes，变成定语从句时，只不过将their改成whose就行了。,

29、23. These people once had fame and fortune; now _ is left to them is utter poverty. (02/6/61) A) all that B) all which C) all what D) that all A) 题意：这些人一度曾拥有名声和财富，现在剩下的只有贫穷了。 解析：that is left to them作all的定语从句。,重点四 名词性从句,重点四 名词性从句,I. 考点分析名词性从句考的最多的是what与that的区别。 II. 知识点名词性从句包括：主语从句、宾语从句、表语从句、同位语从句，多由连

30、词that，wh- 疑问词或由what，whatever等关系代词引导，其中同位语从句在四级考试中最常见。,1. 主语从句,1) 主语从句在句子中充当主语，句子的谓语动词用第三人称单数。如： Why he refused to work with you is still mystery. Whoever comes is welcome. 2) 主语从句前的that不能省略，仅起连接作用，有时为了保持句子平衡，that从句后置，而由it作形式主语。如： That he became a lawyer may have been due to his mothers influence. It

31、 is not true that he has moved to New York.,2. 宾语从句,2. 宾语从句在句子中充当宾语，如： I dont know where the sound came from. Dont be satisfied with what you have achieved. 3.表语从句 3当从句放在系动词 be, look, remain, seem等后即构成表语从句。 The trouble is that I have lost his address. It seemed that the night would never end.,4. 同位语

32、从句,1) 同位语从句是对与之同位的名词中心词作进一步解释，能接名词性从句的常见名词有: idea, fact, news, belief, hope, evidence, opinion, problem, truth, answer, proposal, theory, decision, discovery, problem, thought, understanding 等。 The news that he has passed the examination is exciting. 2) 同位语从句与定语从句的区别在于：定语从句是对先行词加以修饰、限制，而同位语从句时说明名词中心

33、词的具体内容；that在定语从句中充当成分，为关系代词，而在同位语从句中不做任何成分,仅起连词作用。如： The fact that we talked about is very important. (定语从句) The fact that he succeeded in the experiment pleased everybody.( 同位语从句),5. whether与if 在名词性从句中的用法区别,if一般只用于引导宾语从句，而 whether可引导包括宾语从句在内的其他名词从句。 1) 连词whether引导的主语从句，表语从句不能用if来替换。 Whether he will

34、 attend the meeting is uncertain. The question is whether he will come. 2) 宾语从句中，whether常与or not搭配，可以说whether or not，而不说if or not。 I dont care whether or not she will attend the meeting. 3) whether可用在介词后，或带to不定式前，if则不可。 She doesnt know whether to get married now or wait. I havent settled the questio

35、n of whether Ill go back home. 4）某些动词后面(如discuss)只能用whether ，不用if。 We discussed whether we should go on climbing.,四级真题 名词性从句,1. _ men have learned much from the behavior of animals is barely new. (93/01/67) A) That B) Those C) What D) Whether A) 题意：人类从动物行为中学到很多东西这一点还很少为人所知。 解析：句中that引导一个主语从句。 2. An

36、Olympic Marathon is 26 miles and 385 yards, approximately _ from Marathon to Athens. (95/06/49) A) distance B) is the distance C) the distance D) the distance is C) 题意：奥林匹克马拉松赛跑为26英里385码，约为从马拉松到雅典的距离。 解析：名词短语approximately the distance from Marathon to Athens 用来进一步说明26 miles and 385 yards究竟有多长，在语法上叫做

37、同位语。若选择B) 或D)项，则前后两句之间应有or或and之类的连接词。,3. By success I dont mean _ usually thought of when that word is used. (96/06/49) A) what is B) that we C) as you D) all is A) 题意：我所说的“成功”一词，并不是指我们使用它时通常所想到的东西。 解析：主句中谓语动词mean缺少宾语，从句中的谓语动词thought of缺少主语，因此，划线部分所需要的词既引导宾语从句，又在宾语从句中充当主语，在这种情况下，应使用what连接句子。 4. The

38、mere fact _ most people believe nuclear war would be madness does not mean that it will not occur. (97/06/53) A) what B) which C) that D) why C) 题意：大多数人认为核战争是疯狂行为，但这一点并不意味着核战争不会发生。 解析：“the mere fact”与that引导的从句是同位语。从句中基本成分齐全，故不能使用which构成定语从句。C正确。,5. Although Anne is happy with her success she wonders

39、 _ will happen to her private life. (00/01/50) A) this B) it C) what D) that C) 题意：Anne对取得的成功感到高兴，但是不知道她的私人生活会发生什么事。 解析：全句是个主从复合句，由although引出的是让步状语从句，主句中wonder又带有一个宾语从句。根据主句的意思空格中应填入表示疑问意思的词。 6. We agreed to accept _ they thought was the best tourist guide. (00/01/53) A) whichever B) whoever C) what

40、ever D) whomever B) 题意：我们同意接受任何人，只要他们认为是最好的导游。 解析：宾语从句。分析句子结构，空格处应作accept的宾语，同时作was的主语，且表示人，所以应选B项。例如：Whoever is responsible for this will be punished. 对此事负有责任的人要受到处罚。D) whomever是whoever的宾格，相当于anyone whom，在句中只能作宾语用。例如：You may invite whomever you like. 你喜欢的任何人都可以邀请。,7. There are signs _ restaurants a

41、re becoming more popular with families. (00/06/37) A) that B) which C) in which D) whose A) 题意：有迹象表明，饭店越来越受到家庭的青睐。 解析：同位语从句。根据句意，从句只是对“signs”做解释说明，并未对这个词起限定修饰作用，也就是说，“signs”在从句中并不作任何成分。由此，我们可以看出这里的从句应该是同位语从句，而不是定语从句。 8. The basic features of the communication process are identified in one question:

42、Who says _ through what channel to whom? (01/01/52) A) what B) when C) how D) such A) 题意：交际过程的基本特征可以归结为一个问题：谁说了什么，通过何种途径，对象是谁？ 解析：特殊句式。本题空格处应该做句子的宾语。how是疑问副词，不能作say的宾语；when表示“什么时候”，不合句意；such作代词是指上下文中提到的事物，代入句中不合适。,9.The mother didnt know who _ for the broken glass. (02/01/64) A) blamed B) to blame C

43、) be blamed D) would blame B) 题意：这位母亲不知道该怪谁打破了玻璃。 解析：宾语从句省略。to blame表示被动意义，这是blame的一个特殊用法。blame sb. for sth.“因为而责备某人”；blame sth. on /upon sb.“把归咎于某人”。 10. How is it _ your roommates request and yours are identical? (02/06/50) A) if B) so C) what D) that D) 题意：你室友的请求和你的是一样的，这怎么回事？ 解析：主语从句。这是一道略带口语化的考

44、题。It在题句中充当形式主语。由that引导的句子构成主语从句，作句中真正主语。,11. They always give the vacant seats to _ comes first.(02/12/51) A)whoever B)whomeverC)who D) whom A) 题意：他们把空座给最早来的人，不管他是谁。 解析：在特殊疑问词后加上-ever表示“不管”，此处要填的词作“comes”的主语，应是主格，B)、C)都是宾格，不可以。其实C)也可说得过去，但不如A)好。,重点五 状语从句,重点五 状语从句,I. 考点分析状语从句与连词有密切的关系。重中之重是as作“虽然”时候的

45、用法，要把修饰语提前到从句开头，但主谓并不倒装。如： Old as she was, she was quiet energetic. II. 知识点,1时间状语从句,1) 常见关联词有 when, whenever, while, as, before, after 等。 2）注意 notuntil 正常结构、倒装结构、强调结构、和until置于句首的用法。 He didnt go to sleep until he had finished his homework. （正常结构） Not until he had finished his homework did he go to sl

46、eep. （倒装结构） It was not until he had finished his homework that he went to sleep.（强调结构） Until he had finished his homework he didnt go to sleep. （until置于句首） 3）表示“一就”的连词：once, as soon as, hardly/ s carcelywhen, no soonerthan, the minute, the moment, the instant, immediately, directly, instantly 4） 其他表

47、示时间的短语还有：every time, next time, the day 等。,2地点状语从句,2地点状语从句通常由where, wherever引导 如： Where there is a will, there is a way.,3原因状语从句,1) 通常由because, as ,since引导, 三者区别： because 语气最强，重在交待原因，以why引导的疑问句只能because用来回答；其前可用only, just等词强调；可用在 It isthat强调句型中。如：You shouldnt get angry just because some people speak

48、 ill of you. as 一词口气最弱，表示明显的原因。如：As she was in a hurry, she left her key in the car. since 表示人们已知的事实，所以常译成“既然”。如：Since everyone is here, lets get started. 另外，for属并列连词，不能位于句首，是对前一分句加以解释或说明。如：It must have rained last night, for the yard is wet. 2）与since相近，seeing that, now that, considering that, given

49、 that 都有“鉴于某个事实、考虑到”的意思，此外，in that， not thatbut that，on the grounds that 均可表示原因。,4.目的状语从句,目的状语从句引导词有 so that, in order that,( 从句中常有情态助动词may/might, shall/should, will/would, can/could) in case, for fear that, lest, (从句中常有should, might等助动词) for the purpose that等。 5.结果状语从句 结果状语从句引导词有so that, such that,

50、 sothat, suchthat, to the degree/extent that等。 6.条件状语从句 条件状语从句分为真实和非真实两种。（非真实条件状语从句详见虚拟语气部分）引导词有if, unless, as/so long as, once, in case, provided/providing that, suppose, supposing that, on condition that,7方式状语从句,方式状语从句引导词有as, as if, as though, the way. 如：Do it the way you were taught. 8比较状语从句 详见比较

51、部分 9让步状语从句 让步状语从句引导词有though, although, as, even though, even if, wh-ever(no matter how/what/who) ，while (while位于句首，一般意为“尽管”) 如：While we dont agree we continue to be friends. 关于让步状语从句的倒装，详见倒装部分,四级真题 状语从句,1. If you smoke in a non-smoking section people _. (93/01/41) A) have objected B) objected C) mus

52、t objected D) will object D) 题意：如果你在非吸烟区吸烟，人们就会反对。 解析：if引导的条件状语从句中应遵循“主将从现”的格式。 2. A man escaped from the prison last night. It was a long time _ the guards discovered what had happened. (93/06/50) A) before B) until C) since D) when A) 题意：昨晚有人越狱逃跑了，警卫直到很久以后才发现发生了什么事。 解析：句型It was a long time before意

53、为“直到很久以后才”，其他选项都不符合逻辑。,3. Government cannot operate effectively _ it is free from such interference. (94/01/53) A)so long as B) so that C) unless D) because C) 题意：除非不受干涉，否则政府工作无法有效运转。 解析：4个选项中只有unless “除非”符合题意。其余三项词义分别为：A) so long as “只要”，B) so that “为的是”，D) because“因为”。 4. Ill accept any job _I don

54、t have to get up early. (94/01/60) A) lestB) as long as C) in case D) though B) 题意：只要不必早起，我可以接受任何工作。 解析：4个选项中只有so long as “只要”符合题意，引导条件状语从句。其余三项词义分别为：A) lest“以防”，C) in case“假使，以防” ，D) though“尽管”。,5. The computer has brought about surprising technological changes _ we organize and produce information

55、. (94/01/64) A) in a way B) in the way C) in that way D) in no way B) 题意：计算机在组织和产出信息方面为我们带来了惊人的技术革新。 解析：in the way表示“在方面”，后面常接定语从句，而短语in a way“在某种程度上”，in that way“用那种方法”，in no way“决不”都不符合题意。 6. Not that John doesnt want to help you, _its beyond his power. (95/01/54) A) but that B) for that C) and th

56、at D) in that A) 题意：不是因为约翰不想帮你，而是因为他力所不及。 解析：Not thatbut that是一固定结构，表示“不是因为而是因为”。,7. _ they reached the center of the city, they stopped the car at a bar. (95/01/69) A) Before a mile or so when B) For a mile or so after C) Further than a mile or so D) A mile or so before D) 题意：在离市中心一英里左右的酒吧旁他们停下了车。

57、解析：本题可采用排除法来做。A)B)两项连词混乱，可首先排除，C)中没有可引导的连词，故只有D)正确。 8. _ quite recently, most mothers in Britain did not take paid work outside the home. (95/06/52) A) Before B) Until C) From D) Since B) 题意：英国大多数做母亲的人直到最近才外出从事有偿劳动。 解析：4个选项中只有until可以用于副词recently之前。另外，主句谓语若含否定意义，until表示“直到才”，用在此处意思合适。,9. Scientists s

58、ay it may be five or ten years _ it is possible to test this medicine on human patients. (95/06/54) A) since B) before C) after D) when B) 题意：科学家认为，这种药物可能需要5到10年时间才能在人体上做实验。 解析：句型it is/was (time)before 表示“花了多长时间才发生某事” 10. Liquids are like solids _ they have a definite volume. (95/06/58) A) in that B

59、) for that C) with that D) at that A) 题意：液体和固体相类似是在于它们都有一定的体积。 解析：In that表示“因为”。实际上，起由that引导的介词宾语只能和in，but，except等少数介词连用。,11. Doing your homework is a sure way to improve your test scores, and this is especially truth _ it comes to classroom tests. (96/01/36) A) when B) since C) before D) after A) 题意：做好家庭作业是提高你考试成绩的切实有效的方法，在课堂测验时更是如此。 解析：固定句型When it comes to的意思是“当涉及时，当谈到时”。 12. Careful surveys have indicated that as