OG逻辑菜鸟分类手册之削弱题，其中包括72道OG削弱题，按前提结论型、因果型、措施目的型及其它型来组织，每种类型的题目又根据解题方法的进一步分类。大家可以点击“视图—>文档结构图”进行查看。
一、前提结论型
A.前提不充分/它因削弱
1、承认前提，它因反对结论(前提与结论关系不密切)
18. A proposed ordinance requires the installation in new homes of sprinklers automatically triggered by the presence of a fire. However, a home builder argued that because more than ninety percent of residential fires are extinguished by a household member, residential sprinklers would only marginally decrease property damage caused by residential fires. 结论：大部分火灾由人灭，因此喷头在保护财产上无效 (削)还有小部分火灾导致大损失(论据中的漏洞)
Which of the following, if true, would most seriously weaken the home builder’s argument?
A. most individuals have no formal training in how to extinguish fires. —>灭火并非要专业训练
B. Since new homes are only a tiny percentage of available housing in the city, the new ordinance would be extremely narrow in scope. —>范围小，保护财产的effectiveness差，加强
C. The installation of smoke detectors in new residences costs significantly less than the installation of sprinklers. —>与costs无关
D. In the city where the ordinance was proposed, the average time required by the fire department to respond to a fire was less than the national average. —>与消防队无关 E
E. The largest proportion of property damage that results from residential fires is caused by fires that start when no household member is present.
18.
The home builder reasons from evidence about most residential fires to a conclusion about the effectiveness of sprinklers in preventing property damage. But this reasoning is faulty because of the possibility that most of the property damage results from the minority of fires excluded from the builder’s evidence. That possibility is realized if E is true. Thus, E is the best answer.
Because the builder’s argument concerns neither the cost of installing sprinklers not a comparison with fire department performance in other locations, C and D are irrelevant. The evidence the home builder cites suggests that formal training is not needed in order to extinguish fires. So A is not the correct answer. B supports the builder’s view that requiring sprinklers would have a limited effect.
52. Most consumers do not get much use out of the sports equipment they purchase. For example, seventeen percent of the adults in the United States own jogging shoes, but only forty-five percent of the owners jog more than once a year, and only seventeen percent jog more than once a week. —>前提：跑步鞋没怎么用来跑步;结论：运动设施没有被much use(一般结论要比前提宽，入手点之一即是找其中的差距)
Which of the following, if true, casts most doubt on the claim that most consumers get little use out of the sports equipment they purchase?
(A) Joggers are most susceptible to sports injuries during the first six months in which they jog. —>受伤当然不会再去跑步，不对
(B) Joggers often exaggerate the frequency with which they jog in surveys designed to elicit such information. —>我觉得有些加强的意思
(C) Many consumers purchase jogging shoes for use in activities other than jogging.
(D) Consumers who take up jogging often purchase an athletic shoe that can be used in other sports. —>这些人属于经常运动的，是原调查中的未表示出来的那部分人，无关 C
(E) Joggers who jog more than once a week are often active participants in other sports as well. —>同D
52.
The claim that most consumers do not get much use out of the sports equipment they purchase is supported by the infrequency with which jogging shoes are used for jogging. This reasoning overlooks the possibility that jogging shoes are used for other purposes; thus, choice C is the best answer.
Because injured joggers are less likely to use their jogging shoes, choice A is inappropriate. If B is true, joggers use their jogging shoes even less than the study cited states. So choice B is inappropriate. Because the consumers and joggers mentioned in D and E respectively are most likely to be among those who frequently use sports equipment and whose existence the argument concedes, D and E are inappropriate.
68. A drug that is highly effective in treating many types of infection can, at present, be obtained only from the bark of the ibora, a tree that is quite rare in the wild. It takes the bark of 5,000 tree to make one kilogram of the drug. It follows, therefore, that continued production of the drug must inevitably lead to the ibora’s extinction. 结论：持续生产一定会导致灭绝;削：不一定会导致灭绝(给出原因)
Which of the following, if true, most seriously weakens the argument above?
(A) The drug made from ibora bark is dispensed to doctors from a central authority. —>跟如何分配无关
(B) The drug made from ibora bark is expensive to produce. —>生产成本高并不能使树不extinct
(C) The leaves of the ibora are used in a number of medical products. —>如果树叶也有用，则extinction的结论得以加强
(D) The ibora can be propagated from cuttings and grown under cultivation. —>可以人工繁殖当然持续生产不会使之extinct(要把选项加入前提及特别是结论中去考虑，要问自己，如果D成立的话，对前提及结论有没有影响?有正影响/负影响?) D
(E) The ibora generally grows in largely inaccessible places. —>摘不到树皮跟能不能continued production有关，但跟持续生产后产生的结果无关
68.
If the ibora can be successfully cultivated, it is possible to continue production of the drug without threatening the ibora with extinction. Therefore, choice D is the best answer.
If production continues, the method for distributing the drug aftr it has been produced (choice A) is not likely, on its own, to have consequences for the continued existence of the ibora. Nor is the price of the drug (choice B). If the leaves of the ibora also have a use (choice C), the threat of extinction is strengthened rather than weakened. Finally, if the ibora is largely inaccessible (choice E), this bears on the question of whether production of the drug could continue, not on what would happen if it did continue.
105. Treatment for hypertension forestalls certain medical expenses by preventing strokes and heart disease. Yet any money so saved amounts to only one-fourth of the expenditures required to treat the hypertensive population. Therefore, there is no economic justification for preventive treatment for hypertension.
Which of the following, if true, is most damaging to the conclusion above?
(A) The many fatal strokes and heart attacks resulting from untreated hypertension cause insignificant medical expenditures but large economic losses of other sorts. —>它因削弱
(B) The cost, per patient, of preventive treatment for hypertension would remain constant even if such treatment were instituted on a large scale. —>规模不经济，加强
(C) In matters of health care, economic considerations should ideally not be dominant. —>说的是经济原因，跟非经济原因无关
(D) Effective prevention presupposes early diagnosis, and programs to ensure early diagnosis are costly. —>更贵，加强 A
(E) The net savings in medical resources achieved by some preventive health measures are smaller than the net losses attributable to certain other measures of this kind. —>没有说对H病的治疗，属无关
105.
If the results of untreated hypertension cause large economic losses, as choice A claims, then the treatment of hypertension may well be economically justifiable. Therefore choice A is most damaging to the conclusion and is the best answer.
Choices B and D tend to support the conclusion; choice B says that making preventive treatment widespread would not introduce economies of scale, and choice D identifies one aspect of prevention that is both costly and essential. Choice C undermines a different conclusion-that society should not support treatment for hypertension-but does not damage the conclusion actually drawn. The fact that different preventive health measures have different economic consequences (choice E) gives no specific information about treatment for hypertension, and so cannot affect the conclusion drawn.
110. Robot satellites relay important communications and identify weather patterns. Because the satellites can be repaired only in orbit, astronauts are needed to repair them. Without repairs, the satellites would eventually malfunction. Therefore, space flights carrying astronauts must continue. —>逻辑链：要保证卫星正常工作，必须继续载人飞船(去维修);削必要条件：不要继续飞行(说出原因)
Which of the following, if true, would most seriously weaken the argument above?
(A) Satellites falling from orbit because of malfunctions burn up in the atmosphere. —>强调不修理的后果，但并不意味着一定要用载人飞船来完成
(B) Although satellites are indispensable in the identification of weather patterns, weather forecasters also make some use of computer projections to identify weather patters. —>跟天气预报员可以不用卫星有何关系?
(C) The government, responding to public pressure, has decided to cut the budget for space flights and put more money into social welfare programs. —>指出“没钱飞行”，这只是一个捍卫该计划的问题(“什么?不给钱让我们上天了?打个电话给小布，看看他是怎么搞的?上天没钱不行!”)，并不是反对“维修必须派载人飞船去”理由，看似相关，实则跟逻辑链无关
(D) Repair of satellites requires heavy equipment, which adds to the amount of fuel needed to lift a spaceship carrying astronauts into orbit. —>只说了载人飞行本身有困难，没说不能克服 E
(E) Technical obsolescence of robot satellites makes repairing them more costly and less practical than sending new, improved satellites into orbit. —>说出不需要继续飞行的原因
110.
The argument presented in support of manned spaceflights rests on the notion that astronauts are needed to repair satellites. If sending up a new, improved satellite is less costly and more practical than repairing an old one, however, as choice E states, the argument is weakened. Choice E is therefore the best answer.
None of the other choices gives any reason to think that manned spaceflights are not a necessity, so none of them is correct. Choice A describes one consequence of not repairing satellites, while choice B refers to another tool that weather forecasters use in addition to satellites. Choice C describes the circumstances in which defending manned spaceflight has become an issue, and choice D states a practical, but not insuperable, difficulty faced by flights intended for repair projects.
111. Advocates of a large-scale space-defense research project conclude that it will represent a net benefit to civilian business. They say that since government-sponsored research will have civilian applications, civilian businesses will reap the rewards of government-developed technology.
Each of the following, if true, raises a consideration arguing against the conclusion above, EXCEPT:
(A) The development of cost-efficient manufacturing techniques is of the highest priority for civilian business and would be neglected if resources go to military projects, which do not emphasize cost efficiency.
(B) Scientific and engineering talent needed by civilian business will be absorbed by the large-scale project.
(C) Many civilian businesses will receive subcontracts to provide materials and products needed by the research project. —>是加强此计划而非削弱
(D) If government research money is devoted to the space project, it will not be available for specifically targeted needs of civilian business, where it could be more efficiently used. C
(E) The increase in taxes or government debt needed to finance the project will severely reduce the vitality of the civilian economy.
111.
Choice C describes a benefit to civilian business of the research project, and therefore provides support to the conclusion that the project will represent a net benefit to civilian business, rather than arguing against that conclusion. Choice C is therefore the best answer.
Each of the other choices presents a disadvantage of the project for civilian business that might outweigh the stated benefit, so none is correct. Cost efficiency, vital to civilian business, would be neglected (choice A); technical talent needed by civilian business would be unavailable (choice B); the government funding could be used more efficiently if directed specifically to the needs of civilian business (choice D); and the burden of financing the project would hamper civilian business (choice E).
125. Unlike the wholesale price of raw wool, the wholesale price of raw cotton has fallen considerably in the last year. Thus, although the retail price of cotton clothing at retail clothing stores has not yet fallen, it will inevitably fall. —>削：零售价不会降低
Which of the following, if true, most seriously weakens the argument above?
(A) The cost of processing raw cotton for cloth has increased during the last year. —>运作成本上升，它因削弱
(B) The wholesale price of raw wool is typically higher than that of the same volume of raw cotton. —>比较无意义
(C) The operating costs of the average retail clothing store have remained constant during the last year. —>与文意相反(批发价下降，成本应下降才对，可是这里成本却没变)
(D) Changes in retail prices always lag behind changes in wholesale prices. —>加强(只是时间差而已) A
(E) The cost of harvesting raw cotton has increased in the last year. —>要从批发价推导到零售价，跟批发之前的收割成本无关
125.
The argument concludes that declining wholesale prices for raw cotton, will produce declining retail prices for cotton products. Choice A weakens the argument by pointing to higher processing costs for raw cotton, which could offset lower wholesale prices. A is therefore the best answer.
Choice B is incorrect because the argument focuses on price changes, not on relative price levels. Choice C is incorrect because it in effect denies that lower wholesale prices for cotton have been offset by rising operating costs. Choice D is incorrect because it is entirely consistent with the prediction made. Choice E is incorrect because the rising cost of harvesting raw cotton, though possibly affecting wholesale prices, cannot affect the relationship between wholesale and retail prices.(注意是哪个逻辑主体跟哪个逻辑主体间的关系，逻辑链一定要清楚，否则很容易被搞混!)
147. Crops can be traded on the futures market before they are harvested. If a poor corn harvest is predicted, prices of corn futures rise; if a bountiful corn harvest is predicted, prices of corn futures fall. This morning meteorologists are predicting much-needed rain for the corn-growing region starting tomorrow. Therefore, since adequate moisture is essential for the current crop’s survival, prices of corn futures will fall sharply today. 一定下降;削：不一定下降
Which of the following, if true, most weakens the argument above?
(A) Corn that does not receive adequate moisture during its critical pollination stage will not produce a bountiful harvest. —>只是背景知识，与原文吻合
(B) Futures prices for corn have been fluctuating more dramatically this season than last season. —>谷物的价格不能影响今年的收成(注意原文的逻辑链：有雨-收成好-价格低)
(C) The rain that meteorologists predicted for tomorrow is expected to extend well beyond the corn-growing region. —>C使得整个生长季节都有雨似乎更为确定(如果确证则收成好，价格下降，支持)
(D) Agriculture experts announced today that a disease that has devastated some of the corn crop will spread widely before the end of the growing season. —>它因削弱 D
(E) Most people who trade in corn futures rarely take physical possession of the corn they trade. —>只说明期货交易人的细节，不能说明雨季是否能使谷物数量发生变化，同B(没有影响原文的逻辑链)
147.
The argument, in predicting a drop in the price of corn futures, relies on news suggesting a good-sized corn crop. This prediction is undermined if there is, at the same time, news suggesting a small crop. Choice D presents such news and is therefore the best answer.
Choice A provides background information describing a stage at which rains are essential, and choice C makes rain over the entire corn-growing area seem more certain. Both are fully compatible with the argument and do nothing to weaken it. Past price changes (choice B) and details of who handles harvested corn (choice E) cannot affect the eventual size of this year’s corn crop, so neither is relevant to the argument.
158. In comparison to the standard typewriter keyboard, the EFCO keyboard, which places the most-used keys nearest the typist’s strongest fingers, allows faster typing and results in less fatigue, Therefore, replacement of standard keyboards with the EFCO keyboard will result in an immediate reduction of typing costs.
Which of the following, if true, would most weaken the conclusion drawn above?
(A) People who use both standard and EFCO keyboards report greater difficulty in the transition from the EFCO keyboard to the standard keyboard than in the transition from the standard keyboard to the EFCO keyboard. —>用新的比用旧的更容易，无关
(B) EFCO keyboards are no more expensive to manufacture than are standard keyboards and require less frequent repair than do standard keyboards. —>新论据证明新的生产成本和修理成本更低，它因加强
(C) The number of businesses and government agencies that use EFCO keyboards is increasing each year. —>新的有优势，受欢迎，与成本的立即下降吻合(隐含假设：成本不下降，企业不会用-都是经济人)
(D) The more training and experience an employee has had with the standard keyboard, the more costly it is to train that employee to use the EFCO keyboard. —>用新的在短期内(培训)成本会上升，它因削弱 D
(E) Novice typists can learn to use the EFCO keyboard in about the same amount of time it takes them to learn to use the standard keyboard. —>学习的时间同样长，它因不变，加强
158.
Choice D, the best answer, undermines the conclusion by pointing to a serious short-term cost of replacing standard keyboards with EFCO keyboards. The employees who are probably the most productive currently, those with the most training and experience, will cause the greatest retraining costs, according to choice D.
Choice A, by contrast, suggests that the transition to the EFCO keyboard is comparatively easy, at least for typists already experienced with both types of keyboards. Choices B and E both eliminate possible sources of increased expense associated with the EFCO keyboard, namely equipment expenses (choice B) and training of new typists (choice E). Choice C, which suggest that some offices have found the switch advantageous, is consistent with there being an immediate reduction of typing costs.
183.Editorial:
Regulations recently imposed by the government of Risemia call for unprecedented reductions in the amounts of pollutants manufacturers are allowed to discharge into the environment. It will take costly new pollution control equipment requiring expensive maintenance to comply with these regulations. Resultant price increases for Risemian manufactured goods will lead to the loss of some export markets. Clearly, therefore, annual exports of Risemian manufactured goods will in the future occur at diminished levels.
Which of the following, if true, most seriously weakens the argument in the editorial?
(A) The need to comply with the new regulations will stimulate the development within Risemia of new pollution control equipment for which a strong worldwide demand is likely to emerge. —>它因削弱
(B) The proposed regulations include a schedule of fines for noncompliance that escalate steeply in cases of repeated noncompliance. —>不守规定的公司要罚钱，而守规定的公司成本上升，两者皆会削弱出口的竞争力，加强
(C) Savings from utilizing the chemicals captured by the pollution control equipment will remain far below the cost of maintaining the equipment. —>另一个使用新设施的成本问题，削弱出口的竞争力，加强
(D) By international standards, the levels of pollutants currently emitted by some of Risemia’s manufacturing plants are not considered excessive. —>即使排放废气量不超标，但新设备很贵，仍然会使出口受损 A
(E) The stockholders of most Risemia’s manufacturing corporations exert substantial pressure on the corporations to comply with environmental laws. —>加强：遵守规定，出口下降
183.
The passage argues that because new pollution control equipment will reduce he competitiveness of some goods manufactured in Risemia, annual exports will be at a lower level in the future. You are asked to identify something that weakens this argument.
Choice A is the best answer, since if the new pollution control equipment itself becomes a product that Risemian manufacturers can export, the loss of certain other export markets will not necessarily lead to a reduction in exports. Therefore this fact weakens the argument.
Choice B and C both emphasize that Risemian manufacturers will have additional costs whether they comply with the regulations or not, so they increase the likelihood that the manufacturers will be less competitive on world markets. Thus these choices strengthen rather than weaken the argument. Choice D is incorrect; the passage states that the pollution control equipment will be expensive, so even if the level of pollution to be controlled is not excessive, exports will still be more expensive. Choice E strengthens the argument rather than weakens it, since it asserts that the stockholders will encourage Risemian manufacturers to comply with the regulations despite the economic disadvantages of doing so.
188.When demand for a factory’s products is high, more money is spent at the factory for safety precautions and machinery maintenance than when demand is low. Thus the average number of on-the-job accidents per employee each month should be lower during periods when demand is high than when demand is low and less money is available for safety precautions and machinery maintenance. 承认前提，它因削弱结论
Which of the following, if true about a factory when demand for its products is high, casts the most serious doubt on the conclusion drawn above?
(A) Its employees ask for higher wages than they do at other times. —>只能说成本更高，跟结论：平均的事故数量多少的可能性没有直接关系
(B) It s management hires new workers but lacks the time to train them properly. —>它因削弱
(C) Its employees are less likely to lose their jobs than they are at other times. —>员工不太会失去工作跟结论无直接关系
(D) Its management sponsors a monthly safety award for each division in the factory. —>加强：事故会更低 B
(E) Its old machinery is replaced with moderns, automated models. —>新机器可能更安全，没有削弱
188.
The passage concludes that in a factory the average number of on-the-job accidents per employee is likely to decline when demand for the factory’s products is high, on the grounds that more money gets spent on safety measures when demand is high than at other times. You are asked to identify a fact that casts doubt on this conclusion.
Choice B is the best answer. Factory workers who are newly hired and not properly trained are more likely to have on-the-job accidents than are trained and experienced factory workers, so the presence of such workers could very well counteract the benefits of spending more on safety.
That employees ask for higher wages has no direct bearing on how likely they are to have on-the-job accidents, so choice A is not a correct answer. There is no straightforward connection between factory employees’ job security and their likelihood of suffering an on-the-job accident so choice C is not correct. Choice D suggests that at least part of the money spent on safety precautions is spent to reward safe work practices, and so tends to support rather than cast doubt on the conclusion. Since modern, automated machinery is likely to be safer to operate than machinery it replaces, choice E casts no doubt on the conclusion.
192.Mourdet Winery: Danville Winery’s new wine was introduced to compete with our most popular wine, which is sold in a distinctive tall, black bottle. Danville uses a similar bottle. Thus, it is likely that many customers intending to buy our wine will mistakenly buy theirs instead.
Danville Winery: Not so. The two bottles can be readily distinguished: the label on ours, but not on theirs, is gold colored. D的结论：金色-可以分辨;削：即使金色-不能轻易分辨(承认前提，它因反对结论)
Which of the following, if true, most undermines Danville Winery’s response?
(A) Gold is the background color on the label of many of the wines produced by Danville Winery. —>重复说明，加强(金色标签是D酒的特征之一，如果有金色标签的酒，很可能就是D酒)
(B) When the bottles are viewed side by side, Danville Winery’s bottle is perceptibly taller than Mourdet Windery’s. —>指出两种酒另外还有区别，不能削弱D酒(因为逻辑链：金色标签—>容易区别)
(C) Danville Winery, unlike Mourdet Winery, displays its wine’s label prominently in advertisements. —>如果广告中的也加强金色标签，则更有可能这种区别会阻止顾客买错酒，因此加强结论
(D) It is common for occasional purchasers to buy a bottle of wine on the basis of a general impression of the most obvious feature of the bottle. —>至少有一些顾客可能会漏看label的区别而买错酒 D
(E) Many popular wines are sold in bottles of a standard design. —>“从酒瓶的形状可以区别其它酒和M酒”跟“D酒的商标足够醒目可以使人分辩D酒和M酒”无关(注意逻辑链)
192.
Mourdet Winery claims that it will lose customers because Danville Winery has imitated its distinctive bottle. Danville denies this claim, and points out that the two bottles can be told apart by the difference in their labels. You are asked to find something that undermines this response.
Choice D is the best answer. According to this choice, at least some of Mourdet’s occasional customers are likely to overlook the difference in labels and buy Danville’s wine instead of theirs, so Danville’s response to Mourdet’s complaint is undermined.
Choice A supports, rather than undermines, Danville’s response; the gold color is a common feature of Danville’s bottles, so a bottle bearing a gold label is more likely to be recognized as a Danville wine. Choice B provides another respect in which the bottles are different, and does not undermine Danville’s response. If the Danville label is emphasized in advertising, it is more likely rather than less that the difference in labels will help prevent customers from buying the wrong wine, so choice C supports rather than undermines Danville’s response. The fact that some popular wines can be distinguished from Mourdet’s by their bottle shape (choice E) says nothing about whether the difference in labels is enough to prevent consumers from buying Danville’s wine instead of Mourdet’s.(跟逻辑链：从商标可以分辩酒无关)
2、它因解释前提，反对结论(前提与结论关系密切)
67. A greater number of newspapers are sold in Town S than in Town T. Therefore, the citizens of Town S are better informed about major world events than are the citizens of Town T. —>报纸卖得多，所以知道的天下大事也多。(注意结论有三：比较;比较两城居民;比较天下大事的所知)
Each of the following, if true, weakens the conclusion above EXCEPT: —>最好都能同时解释前提(因为前提是已知事实：报纸卖得多，不能被反驳)并反对结论
(A) Town S has a larger population than Town T. —>解释前提：报纸卖得多，反对结论：知道的大事多(因为人口多，因此报纸数量可能被众多的人口所稀释)
(B) Most citizens of Town T work in Town S and buy their newspapers there. —>说明有可能S的报纸多卖，但读的人是T城人
(C) The average citizen of Town S spends less time reading newspapers than does the average citizen of Town T. —>卖得多但读的少
(D) A weekly newspaper restricted to the coverage of local events is published in Town S. —>因为并没有指出在S所卖出的报纸中，有多少比例是天下大事的，有多少是当地的新闻，所以足以迫使作者对“天下大事的了解”作出回应，(这个选项有意思) E
(E) The average newsstand price of newspapers sold in Town S in lower than the average price of newspapers sold in Town T. —>S卖的价钱低，所以卖得多，但并不能就此否认S知道的天下大事就少
67.
The conclusion is based on comparing newspaper sales in Town S and Town T. Four answer choices indicate why greater newspaper sales in S need not imply that citizens of S are better informed about world events. Choice B suggests that many newspapers sold in S inform citizens of T, not S. Choices A and C both show how greater newspaper sales can occur without the average citizen having greater familiarity with the news. Finally, choice D suggests that much newspaper reading in S is not a source of information about world events. The price differential noted in E might help to explain the difference in sales, but it does not undermine the conclusion based on that difference.
Therefore, E is the best answer.
179. A museum has been offered an undocumented statue, supposedly Greek and from the sixth century B.C. Possibly the statue is genuine but undocumented because it was recently unearthed or because it has been privately owned. However, an ancient surface usually has uneven weathering, whereas the surface of this statue has the uniform quality characteristically produced by a chemical bath used by forgers to imitate a weathered surface. Therefore, the statue is probably a forgery.
Which of the following, if true, most seriously weakens the argument?
(A) Museums can accept a recently unearthed statue only with valid export documentation from its country of origin. —>M能否接受跟S是否真实无关(不接受就不真实了?)
(B) The subject’s pose and other aspects of the subject’s treatment exhibit all the most common features of Greek statues of the sixth century B.C. —>其它的都相似(真的和假的可能都有某些共同处)，但不能打消前提中的疑问
(C) The chemical bath that forgers use was at one time used by dealers and collectors to remove the splotchy surface appearance of genuinely ancient sculptures. —>它因解释前提，反对结论
(D) Museum officials believe that forgers have no technique that can convincingly simulate the patchy weathering characteristic of the surfaces of ancient sculptures. —>不影响结论 C
(E) An allegedly Roman sculpture with a uniform surface similar to that of the stature being offered to the museum was recently shown to be a forgery. —>用别的例子加强是假的可能性
179.
The passage presents an argument that a particular statue is a forgery because its surface appears to have been given a chemical treatment that forgers typically use. You are then asked to identify the answer choice that weakens the argument.
If the treatment often used by forgers was also used by others on genuine antiquities, the argument that the statue is a forgery is weakened. Therefore choice C is the best answer.
Choice A is not correct because information about whether the museum can accept the statue is not relevant to the question of whether the statue is a forgery, which is the focus of the argument.(找到文章的中心特别是结论在哪，削谁加强谁要有的放夭才行，很多选项靠这个都可排除属无关) Since both genuine antiquities and forgeries would share the most common features, choice B does not cast any doubt on the argument that the statue is a forgery. Choice D indicates that a statue that showed uneven weathering would not be a forgery. Since the statue in question does not have uneven weathering, this choice leaves the argument unaffected, and is therefore incorrect. Choice E reinforces the possibility that the statue is a forgery, so does not weaken the argument.
182.The earliest Mayan pottery found at Colha, in Belize, is about 3,000 years old. Recently, however, 4,500-year-old stone agricultural implements were unearthed at colha. These implements resemble Mayan stone implements of a much later period, also found at Colha. Moreover, the implements’ designs are strikingly different from the designs of stone implements produced by other cultures known to have inhabited the area in prehistoric times. Therefore, there were surely Mayan settlements in Colha 4,500 years ago.
Which of the following, if true, most seriously weakens the argument?
(A) Ceramic ware is not known to have been used by the Maya to make agricultural implements. —>说的是石器的相似性，没有陶器存在不影响结论成立
(B) Carbon dating of corn pollen in Colha indicates that agriculture began there around 4,500 years ago. —>没有指出是哪种人的农业文化
(C) Archaeological evidence indicates that some of the oldest stone implements found at Colha were used to cut away vegetation after controlled burning of trees to open areas of swampland for cultivation. —>没有指出是哪种人在使用这些石器
(D) Successor cultures at a given site often adopt the style of agricultural implements used by earlier inhabitants of the same site. —>有可能是更早时期的另一民族使用该石器，但后来的民族也沿用该石器，它因削弱 D
(E) Many religious and social institutions of the Mayan people who inhabited Colha 3,000 years ago relied on a highly developed system of agricultural symbols. —>说明M人依赖于更早时期发展起来的农业系统，不能削弱结论
182.
The passage argues that the Maya inhabited Colha 4,500 years ago from the fact that 4,500-year-old stone implements from Colha are like much later stone implements that are known to be Mayan. You are asked to identify the choice that weakens the argument.
Choice D suggests a different explanation for the similarity of the implements: the Maya copied the design from an earlier culture. Choice D therefore weakens the argument that the Maya inhabited Colha 4,500 years ago and is thus the best answer.
Since the argument in choice A is based on the similarity of stone implements of different ages, the lack of ceramic agricultural implements leaves the argument unaffected. Choice B and C provide no information about who was practicing agriculture in Colha 4,500 years ago, so they fail to weaken the argument. In choice E the fact that by 3,000 years ago Mayan culture was deeply rooted in agriculture indicates a history that goes back before that date and does nothing to weaken the argument.
187.Automobile Dealer’s Advertisement:
The Highway Traffic Safety Institute reports that the PZ 1000 has the fewest injuries per accident of any car in its class. This shows that the PZ 1000 is one of the safest cars available today.
Which of the following, if true, most seriously weakens the argument in the advertisement?
(A) The Highway Traffic Safety Institute report listed many cars in other classes that had more injuries per accident than did the PZ 1000. —>加强
(B) In recently years many more PZ 1000’s have been sold than have any other kind of car in its class. —>注意：B不是加强，是无关，因为这里用的是“事故率”而不是“事故的总数”来对比，因此跟汽车卖出的总数无关
(C) Cars in the class to which the PZ 1000 belongs are more likely to be involved in accidents than are other types of cars. —>同等级其它车更容易引起交通事故，解释为什么别的车事故比P多，同时反对结论(指东打西)
(D) The difference between the number of injuries per accident for the PZ 1000 and that for other cars in its class is quite pronounced. —>只和同类的其它车比较，没有和一般的车比较，无法得知结果如何，即非加强，也非削弱 C
(E) The Highway Traffic Safety Institute issues reports only once a year. —>无关
187.
The advertisement argues that the PZ 1000 is one of the safest cars available, on the basis of the fact that, within its class, the PZ 1000 has the fewest injuries per accident. You are asked to find something that challenges this argument.
According to choice C, the class of cars to which the PZ 1000 belongs is more dangerous than average in a certain respect, so having the lowest injury rate per accident within that class does not count as strong evidence that the PZ 1000 is a highly safe car overall. Therefore this choice weakens the argument, and is the best answer.还有其它选项的分析，见书
157. Companies O and P each have the same number of employees who work the same number of hours per week. According to records maintained by each company, the employees of Company O had fewer job-related accidents last year than did the employees of Company P. Therefore, employees of Company O are less likely to have job-related accidents than are employees of Company P. —>逻辑链：O实际工伤的数量少-(推测)O不太可能有工伤
Which of the following, if true, would most weaken the conclusion above?
(A) The employees of Company P lost more time at work due to job-related accidents than did the employees of Company O. —>论证的应该是工伤数量问题，工伤引起的工时减少只是工伤产生的结果
(B) Company P considered more types of accidents to be job-related than did Company O. —>P比O工伤数量多是另有其因的。如果定义一样多，则工伤可能也会一样多(它因解释前提，但反对结论)
(C) The employees of Company P were sick more often than were the employees of Company O. —>缺少工伤跟生病之间关系的信息，无法予以评估(如果是生病引起的工伤，则可以考虑为它因削弱)
(D) Several employees of Company O each had more than one job-related accident. —>说明任何一个任意胡为的O雇员工伤的机会都要小，支持(比如：O中40%的工伤是由20%的员工引起，而P中80%的工伤是80%的员工引起，因此整体受伤的可能性O小)，都是基于前提给的事实进行推理B
(E) The majority of job-related accidents at Company O involved a single machine. —>说明任何一个任意胡为的O雇员工伤的机会都要小，支持(可能是说：只是一部机器造成大部分的工伤，别的机器不造成工伤，因此整体的工伤可能性会小)
157.
The data used to support the conclusion come from the companies’ own records. Since, however, choice B indicates that, as compared with Company O, Company P tends to overstate the number of job-related accidents, choice B weakens the conclusion drawn and is the best answer.
Choice A does not weaken the conclusion, but is simply a consequence that would be expected given the data. The relevance of employees’ sicknesses (choice C) cannot be assessed without information about the links, if any, between sickness and job-related accidents. Choices D and E both give reasons for predicting a smaller likelihood that any arbitrary employee of Company O will have a job-related accidents, and thus support the conclusion.
166. Last year the rate of inflation was 1.2 percent, but for the current year it has been 4 percent. We can conclude that inflation is on an upward trend and the rate will be still higher next year. —>(今年比去年低，因此今后还会上升)
Which of the following, if true, most seriously weakens the conclusion above?
(A) The inflation figures were computed on the basis of a representative sample of economic data rather than all of the available data. —>只要有代表性就可以，不影响结论成立
(B) Last year a dip in oil prices brought inflation temporarily below its recent stable annual level of 4 percent. —>去年的低是暂时的现象，它因解释前提，反对结论;
(C) Increases in the pay of some workers are tied to the level of inflation, and at an inflation rate of 4 percent or above, these pay raises constitute a force causing further inflation. —>它因加强
(D) The 1.2 percent rate of inflation last year represented a ten-year low. —>去年的通胀率最低，但没有就结论中通胀是要上升还是下降给出明确的结果(去年最低，将来也会低吗?/或者将来会上升?) B
(E) Government intervention cannot affect the rate of inflation to any significant degree. —>(非直接加强)：如果政府无影响力，那么结论“原因是通胀上升”将导致进一步的通胀
166.
According to choice B, last year’s inflation figure was an anomaly, and inflation has returned to its recent stable level. There is thus less reason to conclude that inflation will rise any further, making B the best answer.
So long as the sample on which the figures are based is representative, there is no reason to doubt (=no doubt相信)that they are essentially accurate, so choice A does not affect the argument. Choice C supports the conclusion by suggesting that there are forces in place to push inflation higher, and choice E supports it indirectly by suggesting that the government is powerless to prevent further increase. Finally, choice D by itself has no clearly defined consequences one way or the other with respect to the conclusion.
B.直接削前提
43. With the emergence of biotechnology companies, it was feared that they would impose silence about proprietary(所有权的) results on their in–house researchers and their academic consultants. This constraint, in turn, would slow the development of biological science and engineering. —>结论：保密会减慢生物科学的发展
Which of the following, if true, would tend to weaken most seriously the prediction of scientific secrecy described above?
A. Biotechnological research funded by industry has reached some conclusions that are of major scientific importance. —>加强结论：如果确实“被认定会保密”，有重大发现当然会阻碍科学发展。削弱要从“这种认为不会出现”入手，A没有提供理由来证实“这种认识不会出现”，属于路线型错误
B. When the results of scientific research are kept secret, independent researchers are unable to build on those results. —>同A，强调保密会阻碍科学发展
C. Since the research priorities of biotechnology companies are not the same as those of academic institutions, the financial support of research by such companies distorts the research agenda. —>议程受资金的影响发生改变与保密无关
D. To enhance the companies’ standing in the scientific community, the biotechnology companies encourage employees to publish their results, especially results that are important. —>这些公司的动机是要使自己成为行业领袖，因此鼓励公开专利，削弱前提 D
E. Biotechnology companies devote some of their research resources to problems that are of fundamental scientific importance and that are not expected to produce immediate practical applications. —>“没有立即的现实功用”与原文的“减慢发展速度”意思吻合，不削弱
43.
D weakens the prediction of secrecy by establishing that biotechnology companies have a strong motive to encourage their researchers to publicize results. Therefore, it is the best answer.
A and B support the argument that developments in biological science and engineering would be slowed if the prediction of secrecy were fulfilled, but do not provide any reason to expect that the prediction will not be fulfilled. The distortion of the research agenda asserted in C is not relevant to the question of scientific secrecy. E, which says that biotechnology companies devote some resources to fundamental problems without immediate practical benefits, is merely consistent with that argument and so does not weaken the prediction.
64. The imposition of quotas limiting imported steel will not help the big American steel mills. In fact, the quotas will help “mini-mills” flourish in the United States. Those small domestic mills will take more business from the big American steel mills than would have been taken by the foreign steel mills in the absence of quotas. —>在没进口的情况下，小厂比大厂拿的订单比有进口时被外国厂拿走的订单还多
Which of the following, if true, would cast the most serious doubt on the claim made in the last sentence above?
(A) Quality rather than price is a major factor in determining the type of steel to be used for a particular application. —>没提供足够关于外厂和内厂的产品质量的信息来削弱结论
(B) Foreign steel mills have long produced grades of steel comparable in quality to the steel produced by the big American mills. —>没说小厂(needed by the conclusion)如何
(C) American quotas on imported goods have often induced other countries to impose similar quotas on American goods. —>没提供足够关于其它国家反限制的结果的信息来削弱结论
(D) Domestic “mini-mills” consistently produce better grades of steel than do the big American mills. —>它因加强(小厂的质量更好，因此拿走的订单更多) E
(E) Domestic “mini-mills” produce low-volume, specialized types of steels that are not produced by the big American steel mills. —>生产的产品不同，小厂的订单增加未必是大厂订单的减少(削前提)
64.
If, as choice E asserts, large and small mills produce different types of steels, increasing sales by small mills need not lead to decreasing sales by large one. Thus, choice E casts a serious doubt on the claim and is the best answer.
Choice A does not present enough information about the relative quality of steel from foreign and domestic mills to cast any doubt on the claim. Similarly, choice B does not provide enough information about small American mills, nor does choice C provide enough information about the likely consequences of quotas imposed by foreign countries to cast doubt on the claim. Choice D tends to support the claim, since better steel should sell better than poorest steel.
96.The difficulty with the proposed high-speed train line is that a used plane can be bought for one-third the price of the train line, and the plane, which is just as fast, can fly anywhere. The train would be a fixed linear system, and we live in a world that is spreading out in all directions and in which consumers choose the free-wheel systems (cars, buses, aircraft), which do not have fixed routes. Thus a sufficient market for the train will not exist. —>因为飞机要比火车方便，所以火车没市场
Which of the following, if true, most severely weakens the argument presented above?
(A) Cars, buses, and planes require the efforts of drivers and pilots to guide them, whereas the train will be guided mechanically. —>此因素不会立即影响顾客的选择
(B) Cars and buses are not nearly as fast as the high-speed train will be. —>比的是飞机
(C) Planes are not a free-wheel system because they can fly only between airports, which are less convenient for consumers than the high-speed train’s stations would be. —>削前提：飞机不比火车更方便
(D) The high-speed train line cannot use currently underutilized train stations in large cities. —>加强 C
(E) For long trips, most people prefer to fly rather than to take ground-level transportation. —>加强
96.
The author argues that planes, since they are a free-wheel system, will be preferred to the high-speed train. Choice C weakens the argument by pointing out that planes are not a free-wheel system and are less convenient than the high-speed train would be. Thus C is the best answer.
The special feature of the high-speed train described in A is not one that clearly affects consumer choice one way or the other way. Since it is planes that would compete effectively with the proposed trains, the fact that cars and buses might not do so is irrelevant. Non-availability of certain station (choice D) and the consumer preferences described in choice E tend to make the proposed train less, not more, attractive and so both choices strengthen the argument.
200.Outsourcing is the practice of obtaining from an independent supplier a product or service that a company has previously provided for itself. Since a company’s chief objective is to realize the highest possible year-end profits, any product or service that can be obtained from an independent supplier for less than it would cost the company to provide the product or service on its own should be outsourced. —>结论：只要能外包的部分比自己做便宜，就可以外包出去，因为符合利润原则(IF THEN);削：便宜但不能外包(IF本身有问题)一件事的正反两面都对bottom-line有影响
Which of the following, if true, most seriously weakens the argument?
(A) If a company decides to use independent suppliers for a product, it can generally exploit the vigorous competition arising among several firms that are interested in supplying that product. —>说明外包的好处：竞争使外包公司受益
(B) Successful outsourcing requires a company to provide its suppliers with information about its products and plans that can fall into the hands of its competitors and give them a business advantage. —>如果通过OUTSOURCING使公司的秘密被竞争对手获知，则最终利润可能受损
(C) Certain tasks, such as processing a company’s payroll, are commonly outsourced, whereas others, such as handling the company’s core business, are not. —>哪些业务实际被外包跟论证：哪些业务应该被外包无关(现有做法不影响措施本身的可行性)
(D) For a company to provide a product or service for itself as efficiently as an independent supplier can provide it, the managers involved need to be as expert in the area of that product or service as the people in charge of that product or service at an independent supplier are. —>外包的好处：外包使公司本身员工具备能力 B
(E) When a company decides to use an independent supplier for a product or service, the independent supplier sometimes hires members of the company’s staff who formerly made the product or provided the service that the independent supplier now supplies. —>说明接受外包的公司的普遍作法，但没有指出这种做法对公司有甚坏处
200.
The passage argues that a company should obtain a needed product or service from an outside supplier whenever a comparison between the price the outside supplier asks and the cost of a company’s making that product or service for itself shows the outside supplier’s price to be lower. The reason given is that doing so will lower the company’s cost and so contribute to its profits.
The question asks you to identify the answer choice that weakens this argument. The correct answer, therefore, will give a reason why using an outside supplier might not help the company’s profitability even though the price the outside supplier asks is low.
Choice B is the best answer since the possible leakage of sensitive information to the company’s competitors is a hidden cost of relying on outside suppliers and gives a reason why outsourcing might not, ultimately, enhance profitability even if it offers an immediate reduction in costs.
Choices A and D are incorrect because they present benefits of outsourcing, not drawbacks-choice A refers to competition between independent suppliers, and choice D refers to the experienced management ability available. Information about which tasks are in fact commonly outsourced (choice C) does not affect the argument, which is about what tasks should be outsourced. Choice E points out a common consequence of outsourcing, but presents no disadvantage of this consequence to the company.
201.State spokesperson: Many businesspeople who have not been to our state believe that we have an inadequate road system. Those people are mistaken, as is obvious from the fact that in each of the past six years, our state has spent more money per mile on road improvements than any other state. 直接削前提(自相矛盾)：花钱不一定公路就是好的
Which of the following, if true, most seriously undermines the reasoning in the spokesperson’s argument?
(A) In the spokesperson’s state, spending on road improvements has been increasing more slowly over the past six years than it has in several other states. —>没有说明：“花钱而公路不好”的理由
(B) Adequacy of a state’s road system is generally less important to a businessperson considering doing business there than is the availability of qualified employees. —>虽然此番话是对商人而言，但结论是关于公路是否充足，而不是关于“公路对于吸引商人的重要性”
(C) Over the past six years, numerous businesses have business have moved into the state. —>跟结论无关
(D) In general, the number of miles of road in a state’ road system depends on both the area and the population of the state. —>发言人引用数据的相关性不受D中地区/人口的影响 E
(E) Only states with seriously inadequate road systems need to spend large amounts of money on road improvements. —>即花大钱在公路上的州的公路一定不完善(自己的论据反驳自己的观点)
201.
The spokesperson argues that the state’s road system is not inadequate, since the amount the state spends on road improvement is more, per mile of road, than any other state spends. The question asks you to find the answer choice that most seriously undermines this reasoning. This will be the choice that shows how a large amount of spending on road improvement need not indicate that the road system is good.
Choice E is the best answer. It points out that spending an unusually large amount on road improvements tends to indicate that the roads being improved must be in unusually poor condition.
Choice A is incorrect since it gives no reason for thinking that spending a large amount of money on road improvements is a poor indicator of the quality of the road system. Choice B and C are incorrect. Although the spokesperson’s argument is addressed to businesspeople, it is solely about whether the state’s road system is adequate. The importance of the road system in attracting business to the state is therefore not relevant to this argument (choice B). The number of businesses relocating into or out of the state is also therefore not relevant to the argument (choice C). Choice D is incorrect since the relevance of the statistic that the spokesperson uses about spending per mile of road is not affected by the information provided here about road systems and state size.
170. The proposal to hire ten new police officers in Middletown is quite foolish. There is sufficient funding to pay the salaries of the new officers, but not the salaries of additional court and prison employees to process the increased caseload of arrests and convictions that new officers usually generate.
Which of the following, if true, will most seriously weaken the conclusion drawn above?
(A) Studies have shown that an increase in a city’s police force does not necessarily reduce crime. —>研究理论加强
(B) When one major city increased its police force by 19 percent last year, there were 40 percent more arrests and 13 percent more convictions. —>别的城市例子证明确实会提高成本，加强
(C) If funding for the new police officers’ salaries is approved, support for other city services will have to be reduced during the next fiscal year. —>资金困难，加强
(D) In most United States cities, not all arrests result in convictions, and not all convictions result in prison terms. —>无关，仅仅说明了三者间明显的关系 E
(E) Middletown’s ratio of police officers to citizens has reached a level at which an increase in the number of officers will have a deterrent effect on crime. —>M城增加警力就能阻止犯罪，从而可能阻止更多的费用产生，它因削弱
170.
The passage says that hiring new officers usually brings new court expenses, but according to choice E hiring new officers in Middletown will lead to a reduction in crime and thus, perhaps, a reduction in court and prison expenses. Therefore, choice E weakens the conclusion drawn and is the best answer.
Three of the other choices tend to support claims made in the passage; choice A suggests that arrests will increase, choice B says that in one city arrests did increase, choice C confirms the scarcity of funds. Choice D is irrelevant; it merely states the obvious about rates of arrest, conviction, and imprisonment.
C.结论带IF
2. The average life expectancy for the United States population as a whole is 73.9 years, but children born in Hawaii will live an average of 77 years, and those born in Louisiana, 71.7 years. If a newlywed couple from Louisiana were to begin their family in Hawaii, therefore, their children would be expected to live longer than would be the case if the family remained in Louisiana. 削：它因使得IF发生，THEN不发生
Which of the following, if true, would most seriously weaken the conclusion drawn in the passage?
A. Insurance company statisticians do not believe that moving to Hawaii will significantly lengthen the average Louisianan’s life. —>结论是说出生在H的人的寿命，不是说L州人口的平均寿命，无关
B. The governor of Louisiana has falsely alleged that statistics for his state are inaccurate. —>错误的声明如何能影响结论?
C. The longevity ascribed to Hawaii’s current population is attributable mostly to genetically determined factors. —>它因削弱：整体-个体的演绎错误
D. Thirty percent of all Louisianans can expect to live longer than 77 years. —>只有30%的L人能活过77岁，大部分寿命都比较低，与原文信息与结论一致，不能削弱 C
E. Most of the Hawaiian Islands have levels of air pollution well below the national average for the United States. —>它因加强结论
2.
C is the best answer. This choice suggests that a significant proportion of Hawaii’s population is genetically predisposed to be long lived. Since Louisianans are not necessarily so predisposed, and since the Louisianans’ children will acquire their genetic characteristics from their parents, not from their birthplace, this choice presents a reason to doubt that Hawaiian born children of native Louisianans will have an increased life expectancy. Therefore, this choice is the best answer.
Because the conclusion concerns people born in Hawaii, not the average Louisianan, A does not weaken the conclusion. Because the governor’s allegation is false, it cannot affect the conclusion. D fails to weaken the conclusion because it is consistent with the information given and the conclusion about life expectancy. By suggesting that Hawa
