一、归纳题：从上到下(从原文到答案)

　　①读题1)注意条件句，如if, as long as等，例第二册P203 (20)

　　2)注意有没有否绝对化词，如only，any，no, solely等

　　3)注意有没有数学上的等式、不等式关系或比例(percent, proportion) 等，

　　例第二册第二册P117⒂、P126⒆、P169(1)、P248(14)

　　②判断答案的原则：(1)答案中不能出现原文中没有的新概念(包括新的动词、形容词、名词等，但是需要同义词的出现)

　　(2)若原文在某一信息点上没有绝对化概念，那么答案中也没有

　　(3)不能出现新的比较

　　(4)答案不能和原文信息相违背。

　　例题：第二册P115⑽P116⑾P123⑼P126⒅

　　③推导结构

　　例题第二册P122④，讲义section 1(19题)

　　2)理解命题及常用表达(这一知识点需要好好把握，不仅仅在归纳题中有用， 在逻辑描述题中，逻辑结构一致性，对上文最好的批评等问法中 都出现)

　　原命题和逆否命题为等价命题，逆命题和否命题为等价命题

　　(A→B+C,逆否命题为～B/～C→～A), (A+B→C,则其逆否命题为～C→～A／～B)

　　II. unless :=if not即not A unless B表达为A→B

　　A unless B表达为非A→B

　　only if: A only if B表达为A→B

　　if only: A if only B表达为B→A

　　A is necessary to B: B→A

　　Whenever, whoever, wherever :=if

　　二、Weaken和Support演绎题型(从下到上，即从答案到原文)

　　weaken support

　　Reasoning

　　Premise(前提)，Conclusion(结论)，Reasoning(推理过程，前提到结论的思维

　　变迁)

　　演绎题所面临的是一个“待评价的推理”，也就是从前提到结论的这个推理是否能够成立我是不知道的，我需要对它进行评价。根据问题的不同问法，确定不同的解题态度，问支持，就找一个选项说它可能对，问反对，找一个选项说它不一定对，问假设考虑使结论成立需要什么，哪一个是使其成立的一个必要条件。

　　1.如何正确理解weaken , support

　　①支持：(support),将答案放在论据和结论之间，对原文推理或者结论有支持作用就可以，所以既可非充分又可非必要
       ②驳斥：(weaken)，将答案放在论据和结论之间，对原文推理或者结论有驳斥作用就可以，所以也是既可非充分又可非必要

　　③如何理解充分和必要

　　1.充分：所谓充分条件就是仅有这条件就足以带来结果，不需考虑别的条件了。

　　它是谁成立，谁一定也成立，比如A→B,如果A成立，那么一定有B

　　2.必要：所谓必要条件就是没有这个条件结果一定不对。

　　2.前因后果结构

　　推理中的前提和结论在大多数情况下用因果关系来表示，根据因果关系中的结果成立不成立我们分为两种逻辑结构，前因后果结果和Causal Explanations结构，以后讲的答案方向点区别并不大，但是我们为了利于理解进行这个分类

　　前因后果结构表示：(A——B)

　　从这个原因是否能够得到这个结果？(注意because, since, for等原因引导词)

　　这个方法是否能够达到这个目的？(注意by引导方法，To的不定式引导目的)

　　从这个条件是否能够得到这个结论？(注意if ，when, as long as等引导条件)

　　★注意上面的结果、结论到底能不能够成立，目的到底能不能够达到，还不确定。

　　驳斥、支持方向：

　　A方法可行，P122(7)

　　A-B之间P113(3)、P116(12)

　　A之外因素的影响B P113(2)、P123(11)

　　直接对B说讲义Section 1第4题

　　3.Causal Explanations

　　a.对一个事实的发生、一个现象的存在，一个研究的发现，提出一种解释也就是为什么这个事实会发生呢?为什么这个现象会存在呢?是这个原因导致的

　　b.从一个已知的,已经发生的事实,已经存在的现象中得到一个结论,这个结论其实还是对上面的事实发生、现象存在做出了一种解释

　　★注意上面的结果、事实，现象都是已经发生，已经成立了，问到底是不是这个原因导致的，这也是Causal Explanation结构和前因后果结构最本质的区别，务必仔细体会。

　　Causal Explanation结构的典型引导词：result、due to、reason、attribute to、hypothesize、the explanation is、be responsible for、把这个事实当作B,把这个原因解释当作A，

　　答案方向：这个原因和结果之间的关系？(B-A之间)

　　有没有别的原因来对上面的事实、现象、研究发现作出解释(A之外的其他原因)

　　支持：直接：就是这原因导致结果，具体还可以表现为没有这个原因就没有这个结果。

　　例题：讲义Section 1第1题，P201(12)

　　间接：没有别的原因解释上面的事实或现象

　　驳斥：直接：原因和结果无关，具体表现为有这个原因没有这个结果或者没有这个原因有这个结果

　　例题：P114(7), P115(9)

　　间接：还有别的原因存在解释上面的事实或现象P124(13)

　　如何统一两种结构的答案方向？

　　4.Weaken, Support读题：

　　1)重点是找出原因和结果两句话，如果没有任何原因指示词，那么重点在结论，紧靠结论因果词(therefore ,thus)前面的往往就是原因

　　2)对to的不定式要读出(往往表示为对一个目的提出一个方法)

　　3)对any, all, none, everyone, each, no, in general, on the whole 等词需注意，因可能会为范围差异

　　4)对only, solely加以注意，例：第四册：P18⑿

　　5)对动词的程度修饰，例：第四册：P7⑥

　　5.一些辅助的类型范围差异、数据得结果、因果顺序、比较原则

　　三：“Assumption”题型

　　假设定义：使结论成立的必要条件

　　①读题：和weaken ,support读题方法完全一样，再注意when、if等词语

　　②答案方向：

　　前因后果结构

　　1)因果关系差异概念的桥梁作用(A-B之间)

　　例题：P115(8)、P122(5)、P200(7)、P202(15)、P248(12)、P249(16)

　　2)A可行性或者原因有意义：P228(9)、P246(7)

　　3)没有其他的因素来影响这个结果或者结论P248(12)、P250(18)

　　Causal Explanations:

　　1)没有这个原因就没有这个结果(两者之间)

　　3)没有其他的原因来解释上面的事实或者现象P173(16)、P229(13)

　　★注意此类假设其答案中，很可能会有否定词或 类似否定概念出现

　　注意：和weaken、support一样，这两种结构的答案方向完全可以统一

　　四：“evaluate”题型

　　1.定义：对某个问题两方面的回答(yes and no)或者某个信息两方面的回答，对原文推理如果一方面回答起到支持作用，则另一方面回答起到驳斥作用，如果一方面回答起到驳斥作用，则另一方面回答起到支持作用，这个问题或者信息就对原文有评价作用。

　　★注意一定是yes and no回答都起到作用，如果仅仅一方面回答起到作用，则不是评价

　　2.答案方向：1)直接说，结果和原因之间有没有关系(A-B)例：第二册P172(10)、P198(3)

　　2)A是否可行或者有意义。讲义section 1(11题)

　　3)间接性答案：除A之外是否还有别的因素影响B，例：第四册P104⑨ 或者有没有其他的原因来解释原文中存在的事实或者现象

　　注意：evaluation、assumption和weaken, support的统一

　　五：解释现象

　　1.解释result, situation等，统称为解释结果 具体读出要解释什么，现象是什么，解题要点：抓住要解释的对象，具体发生了什么变化

　　2.解释矛盾，找一个选项说明为什么会存在这种矛盾，解题主要抓住区别点

　　3.答案要明确，满足无推导、无充分性。讲义section 1(第20题)

　　六.完成一段话“题型”

　　找答案需满足：1)在句子意思上满足原文，特别是可将最后一句话补全

　　2)答案必须和原文前半段描述有关系

　　例：第二册：P60⑧P70④P201⒁

　　七.“上文使用何种有疑问技术”题型(逻辑描述)

　　并不是让你找一个选项对上文推理进行驳斥，也不是问原文推理的缺陷，而是让你用逻辑描述的语言来描述一下原文的推导过程。

　　例：第三册P4 (17)第四册P85⑨

　　八、提高(由学生自己去训练培养对weaken support等题的感觉)

　　1.Weaken:——求异2.Support:——求同

　　所谓求同、求异就是答案和原文的一致或不一致，而不是答案中谁与谁一致或不一致，它要求既不要考虑原文的因果之间为什么会如此，也不要考虑答案中因果之间为什么会如此，更不可考虑此答案是如何使得对原文有支持或驳斥作用的，而仅仅辨认在答案满足和原文有关时是保持和原文一致还是不一致，这一点往往对于难题来讲，特别还仅仅剩下两个选项需要辨别的时候，更为有用

　　例：“因为这儿有个人，所以蚂蚁有两条腿。”对这一论证的支持或驳斥不应考虑为什么人和蚂蚁有关，而只考虑在答案中说有人或说蚂蚁两条腿的情况下，找其相同或不同就可以了，如“相邻近处没有人，蚂蚁也有两条腿”，在满足说蚂蚁有两条腿时说的是没有人，和上边论述不一致，因此可weaken同理说“在邻近处没有人，蚂蚁也就无两条腿，”就有support作用，你所需做的仅仅是寻找相同或不同点，仅此而已，大家可由第三册上P1②P2⑼P3⑿P5⒇P28③⑤P29⑿⒂P46⑥P47⑩⒀等题去理解weaken，由第二册上P30⑾P31⒇P45④P48⒂等理解support.

　　九、最后读题

　　GMAT改为机考后，逻辑题长度明显增加，对此除提高阅读能力外(不是阅读技巧) ，主要要做训练看对一段话中在仅读一遍的情况下，究竟哪句话为结论，然后看出和结论相关的直接原因是什么，最后次要地看出和直接原因相关的性质点中，原文提出过什么就可以了，但对于“归纳”题型只能学会一边读一边思考原文的层次是什么，脑中将层次留下，无其他好方法。

　　Section 1

　　1. The town of Stavanger, Norway, was quiet and peaceful until the early 1960’s, when Stavanger became Norway’s center for offshore oil exploration. Between then and now, violent crime and vandalism in Stavanger have greatly increased. Clearly, these social problems are among the results of Stavanger’s oil boom.

　　Which of the following, if it occurred between the early 1960’s and now, gives the strongest support to the argument above?

　　(A) The people of Stavanger rarely regret that their town was chosen to be Norway’s center for offshore oil exploration

　　(B) Norwegian sociologists expressed grave concern about the increase in violent crime and vandalism in Stavanger.

　　(C) Violent crime and vandalism have remained low in Norwegian towns that had no oil boom.

　　(D) Nonviolent crime, drug addiction, and divorce in Stavanger increased approximately as much as violent crime and vandalism did.

　　(E) The oil boom necessitated the building of wider roads for the increased traffic in Stavanger.

　　2. Since 1945 there have been numerous international confrontations as tense as those that precipitated the Second World War, and yet no large-scale conflict has resulted. To explain this, some argue that fear of enormous destruction such as the Second World War produced has had a dramatic deterrent effect.

　　Which of the following, if true, most seriously weakens the deterrent theory mentioned above?

　　(A) After the First World War, the fear of great future destruction was as intense as it was after the Second World war.

　　(B) Psychologists have determined that the fear of retaliation tends to temper aggressiveness among human beings.

　　(C) The Secon d World War was far less destructive than most people generally believe.

　　(D) Fear of repeating the levels of destruction that the Second World War produced is as pervasive today as it was forty years ago.

　　(E) Many of the international confrontations that have occurred since 1945 have involved countries that participated in the Second World War.

　　3. A list of the fifteen operas most frequently performed in recent times includes no works by the nineteenth century German composer Richard Wagner. Although music producers tend to produce what audiences want, relative infrequency of performance probably does not indicate lack of popularity in Wagner’s case, since Wagner’s operas are notoriously expensive to perform on stage.

　　Which of the following, if true, most strongly support the conclusion of the argument above？

　　(A)The list of most frequently performed operas does not include operas produced by small amateur groups.

　　(B)Some opera companies are backed by patrons who are willing to commit large sums of money insgroupsto enjoy lavish productions.

　　(C)All of the fifteen most frequently performed operas of recent times are works that have been popular for at least 75 years.

　　(D)More recordings have been produced recently of the works of Wagner than of the works of any other composer of opera.

　　(E)Operatic works of all kinds have been increasing in popularity in recent years.

　　4. V-shaped walled structures in central Asia were used by prehistoric hunters who drove hoofed animalssintosan enclosure at the point of the V. The central Asians who built these structures probably learned this hunting technique from invader s from southwest Asia, because the arrival of invaders from a region in southwest Asiaswheressimilar structures had long been used coincides roughly with the building of the earliest of such structures in central Asia.

　　Which of the following, if true, most strengthens the argument?

　　(A) Excavations in the central Asian region do not indicate whether invaders from southwest Asia settled permanently in central Asia.

　　(B) The V-shaped structures in central Asia were roughly 70 meters long, whereas the similar structures in southwest Asia were usually over 300 meters long.

　　(C) The walls of the structures in central Asia were made from earth, whereas the walls of the structures in southwest Asia were made of rock.

　　(D) The earliest examples of V-shaped walled structures in central Asia were of an advanced design.

　　(E) Some of the walled structures used for hunting in southwest Asia were built well after the earliest such structures were built in central Asia.

　　5. The average age and racing experience of the drivers at the Indianapolis 500 automobile race increased each year between 1965 and 1980. The reason for the increase is that high-speed racing drivers were living longer than their predecessors. Race-car safety features that reduced the severity of crashes of the kind that formerly took drivers’lives were primarily responsible for the increase in the average age of the Indianapolis 500 competitors.

　　Which of the following, if true, would be most likely to be part of the evidence used to show that safety features on the cars that protected drivers in major crashes were responsible for the i ncrease in the average age of drivers at the Indianapolis race?

　　(A) Younger drivers at high-speed racetracks were involved in major accidents at a slightly higher rate than were older drivers between 1965 and 1980.

　　(B) Major accidents on high-speed racetracks occurred at about the same frequency in the years after 1965 as in the years before 1965.

　　(C) The average age of drivers attempting to qualify for the Indianapolis 500 decreased slightly between 1965 and 1980.

　　(D) Accidents on highways in the United States occurred at about the same frequency in the years after 1965 as in the years before 1965.

　　(E) Other safety features, involving the condition of the racetrack and the uniforms worn by the drivers while driving, were adopted at Indianapolis between 1965 and 1980.

　　6. Calvin: Fire insurance policies are disadvantageous to policyholders. The typical policyholder always pays more in premiums than he or she collects in payments on policies.

　　Lorraine: Yes, but policyholders are still right in thinking that it is to their advantage to hold an insurance policy. The peace of mind that comes fromshavingsan insurance policy is the main advantage to the policyholder.

　　Lorraine addresses Calvin’s argument by

　　(A) Questioning the source of Calvin’s factual information

　　(B) introducing a consideration neglected by Calvin’s argument

　　(C) showing that Calvin’s argument assumes what it sets out to prove

　　(D) challenging the truth of the evidence advanced in Calvin’s argument

　　(E) showing the irrelevance of Calvin’s evidence to the conclusion he draws

　　7.X: When a rare but ser ious industrial accident occurs, people respond by believing that such accidents are becoming more frequent. This belief is irrational. After all, being dealt four aces in a hand of poker, a rare event, hardly increases one’s chances of being dealt four aces in a future hand.

　　Y: To the contrary, the belief is rational because it results in people’s sensing a danger to themselves not previously sensed and taking precautionary actions to prevent similar accidents in the future.

　　Y’s attempt to counter X’s claim is best described by which of the following?

　　(A) It questions the aptness of the analogy drawn by X.

　　(B) It makes apparent X’s failure to consider how people vary in their responses to a serious accident.

　　(C) It shifts the basis for judging rationality to considerations of utility.

　　(D) It offers an alternative explanation of why people form incorrect beliefs.

　　(E) It challenges X’s assumption that the occurrence of a single event is sufficient to change a belief.

　　8.

　　John: It is permissible and even advisable to execute criminals convicted of brutal murders. After all, a publicized execution can serve to deter heinous crimes and thus minimize suffering in the long run. Capital. punishment is a kind of societal self-defense.

　　Mary: You are ignoring the prior issue of whether a state or society has the right to take anyone’s life. If there is no such right. then, the issue of whether capital punishment deters crime is irrelevant. If it were determined dial capital punishment does not serve to deter crime. John’s and Mary’s positions would be affected in which of the following ways?

　　(A) Neither John’s nor Mary’s position would be affected.

　　(B) Both John’s and Mary’s positions would be weakened.

　　(C) Mary’s position would be strengthened but John’s position would not be affected.

　　(D) John’s position would be weakened but Mary’s position would not be affected,

　　(E) John’s position would be weakened and Mary’s position would be strengthened.

　　9. Excluding purchases by businesses, the average amount spent on a factory-new car has risen 30 percent in the last five years. In the average household budget, the proportion spent on car purchases has remained unchanged in that period. Therefore the average household budget must have increased by 30 percent over the last five years.

　  Which of the following is an assumption on which the argument relies？

　　(A)The average number of factory-new cars purchased per household has remained unchanged over the last five years.

　　(B)The average amount spent per car by businesses buying factory-new cars has risen 30 percent in the last five years.

　　(C)The proportion of the average household budget spent on all car-related expenses has remained unchanged over the last five years.

　　(D)The proportion of the average household budget spent on food and housing has remained unchanged over the last five years.

　　(E)The total amount spent nationwide on factory new cars has increased by 30 percent over the last five years.

　　10. Editorial：

       Critics of nuclear power complain about the allegedly serious harm that might result from continued operation of existing nuclear power plants. But such concerns do not justify closing these p lants；after all, their operation has caused no more harm than that caused by pollution generated by coal-and oil-burning power plants, the most important other sources of energy.

　　Which of the following is an assumption on which the argument depends？

　　(A) Existing nuclear power plants should be closed only if it can be conclusively demonstrated that their continued operation is likely to cause harm more serious than the harm their operation has already caused.

　　(B) Closing existing nuclear power plants would require greatly increased reliance on coal-and oil-burning power plants.

　　(C) The harm that has resulted from operation of existing coal and oil-burning power plants has been significant.

　　(D) The harm that a nuclear power plant is likely to cause as it continues to operate can be reliably predicted from the past history of nuclear power plants.

　　(E) The only harm that has resulted from operation of existing coal and oil-burning power plants has resulted from the pollution generated by these plants.

　　(F) Closing existing nuclear power plants would require increased reliance on coal-and oil-burning power plants.

　　11. Sleep deprivation is a known cause of workplace error, and many physicians frequently go without sleep for periods of 24 hours or more. However, few of these physicians have, in the course of a routine examination by a peer, been diagnosed with sleep deprivation. So there is little cause for concern that habitual sleep deprivation will cause widespread physician error.

　　The answer to which of the following questions would be most helpful in evaluating the argument？

　　(A)Do physicians who have been diagnosed with sleep disorders also show signs of other ills not related to sleep deprivation？

　　(B)Is the ability to recognize the symptoms of sleep deprivation in others significantly impaired by habitual sleep deprivation？

　　(C)Do factors other than habitual sleep deprivation ever lead to errors in the workplace on the part of physicians？

　　(D)Of people who have recently been treated by physicians, what percentage believe that many physicians have occasionally suffered from sleep deprivation？

　　(E)Is the incidence of sleep deprivation higher among physicians than it is among other health care workers？

　　12. The organizers of tomorrow’s outdoor concert announced that it will go on tomorrow on schedule unless bad weather is forecast or too few advance tickets are sold. If the concert is canceled, refunds will be made to ticket holders. Since some ticket holders have already been issued refunds even though more than enough advance tickets were sold, it must be the case that bad weather is forecast.

　　Which of the following is an error of reasoning contained in the argument?

　　(A) It proceeds as if a condition, which by itself is enough to guarantee a certain result, is the only condition under which that result would occur.

　　(B) It bases a conclusion that is known to require two conditions on evidence that bears on only one of those conditions.

　　(C) It explains one event as being caused by another event, even though both events must actually have been caused by some third, unidentified
event.

　　(D) It treats evidence for the absence of one condition under which a circumstance would occur as conclusive evidence that that circumstance will not occur.

　　(E) Evidence given to support the conclusion actually undermines it.

　　13. When six out of ten people who had eaten the egg salad at an office party became ill shortly afterward, the leftover egg salad was tested. Testing failed to confirm the presence of any harmful bacteria in the egg salad. It follows that the egg salad was not responsible for the illness of any of the people who ate it.

　　Which of the following is an error in the reasoning of the argument above?

　　(A) Treating the cause of a sequence of events as if it were the result of that sequence of events

　　(B) Rejecting a possible explanation without suggesting an alternative explanation

　　(C) Failing to consider the possibility that those who did not become ill shortly after eating the egg salad became ill later

　　(D) Treating a lack of proof that something is the case as constituting sufficient proof that it is not the case

　　(E) Overlooking the possibility that some people are more susceptible to harmful bacteria than are other people

　　14. Which of the following most logically completes the argument below？

　　In recent years, the proportion of car buyers who buy new cars rather than used cars has declined.Some consumers have attributed this change to an increase in new-car prices.As evidence of the price increase, they cite figures that show that, even adjusting for inflation, the price that the buyer of a new car pays, on average, is far higher now than a few years ago. This evidence is unpersuasive, however, because___

　　(A)the value of a car that is bought new declines much more rapidly than does the value of a car that is bought used

　　(B)after someone has bought a car, it might be several years before that person next buys a car

　　(C)a decline in the proportion of car buyers who buy new cars must necessarily mean that the proportion who buy used cars has increased

　　(D)the relative increase in used-car sales might be explained by the decisions of only a small proportion of all car buyers

　　(E)the change in the average price paid for a new car could result solely from more people’s rejecting inexpensive new cars in favor of used cars

　　15. Which of the following most logically completes the argument below?

　　Alone among living species, human beings experience adolescence, a period of accelerated physical growth prior to full maturity. Whether other hominid species,

　　which are now all extinct and are known only through the fossil record, went through adolescence cannot be known, since _____

　　(A) the minimum acceleration in physical growth that would indicate adolescence might differ cording to species

　　(B) the fossil record, though steadily expanding, will always remain incomplete

　　(C) detecting the adolescent growth spurt requires measurements on the same individual at different ages

　　(D) complete skeletons of extinct hominids are extremely rare

　　(E) human beings might be the first species to benefit from the survival advantages, if any, conferred by adolescence

　　16. Medical personnel who served in heavy combat in a recent war-even those who escaped physical injury-now have lower incomes and higher divorcerates, and score lower on psychological profiles measuring general happiness, than medical personnel who served in less stressful settings during that war. This evidence demonstrates that exposure to heavy-combat situations produces serious adverse effects, even among those who suffered no physical harm.

　　Which of the following, if true, most strengthens the conclusion drawn above?

　　(A) The medical personnel who served in heavy combat had completed significantly less schooling prior to military service than had other medical personnel.

　　(B) The medical personnel who served in heavy combat tended to be younger at the time of their entrysintosmilitary service than were other medical personnel.

　　(C) Parents of medical personnel who served in heavy combat show no significant difference in incomes, divorce rates, or general happiness from parents of other medical personnel.

　　(D) Income levels, divorce rates, and levels of general happiness are the same for the medical personnel who served in heavy combat as they are for construction workers.

　　(E) Medical personnel who served in heavy combat in an earlier war show no significant difference in incomes, divorce rates, or general happiness from other medical personnel who served in that war.

　　17. Jan: People should not go to the new exhibition of Thornton’s paintings. Thornton will be given a portion of the admission proceeds and Thornton, a violent sociopath, should not be supported.

　　Kim: Your recommendation is inconsistent with your actions, because you read poems by poets who also were violent sociopaths.

　　Which of the following, if true, provides the strongest basis for Jan to counter Kim’s argument?

　　(A) Thornton’s portion of the exhibition’s proc eeds are being donated to a cause deemed worthy by Thornton.

　　(B) It is quite difficult, if not impossible, for Jan to discover the behavioral tendencies of the artists Jan reads.

　　(C) Kim does not use products made by companies whose hiring practices Kim finds abhorrent

　　(D) The poets derived no benefit from Jan’s reading their poems.

　　(E) The poets’violent behavior is better known to the public than is Thornton’s violent behavior.

　　18. It is illogical to infer a second and different effect from a cause which is known only by one particular effect. This is incorrect because the inferred effect must necessarily be produced by some different characteristic of the cause than is the observed effect, which already serves entirely to de scribe the cause.

　　Which one of the following arguments makes the same logical error as he one described by the author in the passage?

　　(A) An anonymous donor gave a thousand dollars to our historical society. I would guess that that individual also volunteers at the children’s hospital.

　　(B) The radioactive material caused a genetic mutation, which, in turn, caused the birth defect. Therefore, the radioactive material caused the birth defect.

　　(C) The city orchestra received more funds from the local government this year than ever before. Clearly this administration is more civic-minded than previous ones.

　　(D) If I heat water, which is a liquid, it evaporates. If I heat hundreds of other liquids like water, they evaporate. Therefore, if I heat any liquid like water, it will evaporate.

　　19. Economist: Any country that is economically efficient will generate wealth. Such a country will remain politically stable only if that wealth is distributed equitably.

　　The equitable distribution of wealth puts an end to risk taking, the indispensable precondition of economic efficiency.

　　Which of the following conclusions can be properly drawn an the basis of the statements above

　　(A) No country can indefinitely remain both economically efficient and politically stable.

　　(B) No country can indefinitely remain both politically unstable and wealthy.

　　(C) Economic efficiency is the indispensable precondition for the generation of wealth in a country.

　　(D) Any country in which wealth is distributed equitably will indefinitely remain politically stable.

　　(E) Growing economic efficiency encourages risk taking, which in turn leads to further growth in economic efficiency.

　　20. In the past ten years, there have been several improvements in mountain-climbing equipment.

　　These improvements have made the sport both safer and more enjoyable for experienced climbers. Despite these improvements, however, the rate of mountain- climbing injuries has double in the past ten years.

　　If all of the statements above are true, which of the following, if true, best reconciles their apparent discrepancy?

　　(A) Many climbers, lulledsintosa false sense of security, use the new equipm ent to attempt climbing reats of which they are not capable.

　　(B) Some mountain-climbing injuries are caused by unforeseeable weather conditions.

　　(C)Mountain climbing, although a dangerous sport, does not normally result in injury to the experienced climber

　　(D) In the past ten years there have been improvements in mountain-climbing techniques as we ll as in mountain- climbing equipment.

　　(E) Although the rate of mountain-climbing injuries has increased, the rate of mountain-climbing deaths has not changed.