61. Investigators concluded that human failure was not responsible for the fatal airplane crash last August, and since that time new and more stringent rules for identifying and reporting mechanical problems have been in effect. That accounts for the fact that reports of airplane mechanical problems have increased in frequency by 50 percent since last August.
Which one of the following is an assumption underlying the argument in the passage?
A. Airplane travel is still relatively safe, despite the increase in reported mechanical problems.
B. Mechanical problems in airplanes have increased dramatically since last August.
C. Mechanical problems in airplanes have not increased by 50 percent since last August.
D. Airlines are less reluctant to report mechanical problems than they previously were.
E. Mechanical problems in airplanes have become easier to detect since last August.
A. 文中第一句the fatal airplane crash last August已经客观存在，说明飞机旅行并非相当安全。与文中事实相反。
B. 用于识别和报告机械故障问题的更加严格的新规定已经生效，这才是the fact that reports of airplane mechanical problems have increased in frequency by 50 percent since last August的真正原因。而B选项Mechanical problems in airplanes是它因，削弱结论。
C. 正确。“Mechanical problems in airplanes have increased by 50 percent since last August”是用他因来削弱结论，加上NOT，则是排除他因的假设。
E. become easier to detect无关词。
62. Brushing your teeth regularly no matter which toothpaste you use, will reduce your chances of tooth decay. Scientists have concluded that, when you brush, you reduce tooth decay by removing the film of plaque that forms on teeth and gums. So, you can forget about fluorides: brush your teeth carefully and say goodbye to cavities.
Which one of the following is a criticism of the reasoning in the argument?
A. Brushing with fluoride toothpaste has been shown to reduce tooth decay.
B. The fact that brushing will reduce tooth decay does not show that fluorides are of no value.
C. Few people adequately remove plaque by brushing.
D. People have plaque on their teeth most of the time.
E. Scientists have been wrong about fluorides.
D. Most of the time无关词。问题同C
63. Some good cooks are gourmet cooks who pride themselves on always using extravagantly rich ingredients in elaborate recipes. Some good cooks can be characterized as fast-food cooks. They may use rich ingredients as long as the recipes are easy to follow and take little time. Other good cooks are health food enthusiasts, who are concerned primarily with the nutritional value of food. But even though not all good cooks are big eaters, they all enjoy preparing and serving food.
If the information in the passage is true, which one of the following CANNOT be true?
A. Most good cooks do not use extravagantly rich ingredients.
B. Everyone who enjoys preparing and serving food is a good cook.
C. More good cooks who use extravagantly rich ingredients are big eaters than are good cooks who do not use such ingredients.
D. There are fewer good cooks who enjoy serving and preparing food than there are good cooks who are big eaters.
E. Gourmet cooks, fast-food cooks, and cooks who are health food enthusiasts are all big eaters.
D. 正确。结论：但是即使并非所有的好厨师是big eaters，他们却全都喜欢准备和供应食物。说明喜欢准备和供应食物的好厨师的人数更多，是big eaters的好厨师的人数相比较少。D选项与原文的结论相反。
If the city council institutes new parking regulations, city revenues will surely increase, since studies have conclusively shown that, if such parking regulations are put into effect, there is an increase in parking violations, and an increase in parking violations will result in a greater number of parking fines collected.
64. If the statements in the passage are true, which one of the following must also be true?
A. Unless there is an increase in the number of parking violations in the city, city revenues will not increase.
B. If the city council institutes new parking regulations, the council will fall from favor with the citizens.
C. The city council will institute new parking regulations only if an increase in city revenues can be expected to result.
D. If the city council’s new regulations cause more parking violators to be ticketed, the city revenues will increase.
E. Unless the city institutes a complex system of parking regulations, the city cannot expect traffic violations to increase.
Choice C just repeats the conclusion: institution of new regulations -> increase of city revenues. it fails to fill the gap between institution of regulations and increase of revenues.
new regulations -> more violations-> more fines collected(increase of revenues)
D is correct.
65. According to advertisements, the higher a suntan lotion’s sun protection factor, or SPE, the more protection from sunburn. In order for a suntan lotion to work, however, one has to remember to put it on before going in the sun, put on an adequate amount to cover the skin, and reapply it as needed. Therefore, it really does not matter what SPE a suntan lotion has.
Which one of the following best identifies the error in reasoning made in the passage?
A. It is unreasonable to assume that the only purpose of a suntan lotion is to provide protection from sunburn.
B. Because some people get sunburned more easily than other, the fact that there are different SPEs cannot be ignored.
C. It cannot be concluded that the SPEs is not important just because there are requirements for the application of the suntan lotion.
D. It is unreasonable to assume that all suntan lotions required the same application procedures in order to work effectively.
E. There is no reason to assume that manufacturers are unaware that people sometimes forget to apply suntan lotion before going in the sun.
This is exactly the same as No 62. 只有C明确提出不能因为一样东西有作用就说另外一个东西没作用：准确无误指出了原文论证的漏洞。
A， The passage has nothing to do with the “only purpose”.
B， Because the passage has already make clear that people can apply many times of the lotion for difference people, so the idea in choice B is not a lope hole in the reasoning.
C，By pointing out that it is not right to eliminate the effectiveness of SPEs because there are other requirements.
D，There is no assumption in the passage that all suntan lotions required the same application procedures.
E，Anything about manufactures does not bear on the reasoning in the passage.