费费61、80

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.

答案是C， 答案解释是C取非：Mechanical problems in airplanes have  increased by 50 percent since last August，削约结论，human failure was not responsible for the fatal airplane crash last August, 应该是支持结论呀，因为是Mechanical problems ，所以不是human failure，responsible for the fatal airplane crash！！！支持结论呀？？？？？？

请NN解释一下。

80. Advertisement: Clark brand-name parts are made for cars manufactured in this country. They satisfy all of our government automotive tests-the toughest such tests in the world. With foreign-made parts, you never know which might be reliable and which are cheap look-alikes that are poorly constructed and liable to cost you hundreds of dollars in repairs. Therefore, be smart and insist on brand-name parts by Clark for your car.

The argument requires the assumption that

A.        Clark parts are available only in this country

B.        foreign-made arts are not suitable for cars manufactured in this country

C.        no foreign-made parts satisfy our government standards

D.       parts that satisfy our government standards are not as poorly constructed as cheap foreign made parts

E.        if parts are made for cars manufactured in our country, they are not poorly constructed

答案是D，取非削约。但是取非以后，    parts that satisfy our government standards are as poorly constructed as cheap foreign made parts ==》be smart and insist on brand-name parts by Clark for your car应该是增强呀！！！！

调查人作出结论，去年8月人为疏忽不是造成致命飞机坠毁的原因，并且在那时新的和更严厉的鉴定和报告机械问题的规定开始有效了。这说明了事实，飞机机械问题的报告频率增加50％直到去年8月。（8月前还未到50％）

本题问论点的假设，直接看论点。

第一句是evidence,第二句是argument，assumption是基于第二句argument的fact的假设。而不是第一句

第一句话不是结论，所以你的理解有偏差。