备考四六级考试阅读课堂笔记

3. A necessary cause is ____.

A) one without which it is impossible for the effect to occur

B) one of the causes that can produce the effect

C) one that is enough to make the effect occur

D) none of them

4. Your refrigerator is not working and you have found that the electric power has been cut off.

The power failure is a ____.

A) necessary cause B) sufficient cause

C) contributory cause D) none of them

5. This passage mainly discusses ____.

A) causal reasoning B) classification of cause

C) various types of reasoning D) the causal process

Questions 1 to 5 are based on the following passage.

Another common type of reasoning is the search for causes and results. We want to know whether cigarettes really do cause lung cancer, what cause malnutrition(营养不良), the decay of cities, or the decay of teeth. We are equally interested in effects: what is the effect of sulphur or lead in the atmosphere, of oil spills and raw sewage to the cause and then relate that cause to another effect. This kind of reasoning is called, for short, effect to effect. It is quite common to reason through an extensive chain of causal relations. When the lights go out we might reason in the following causal chain: lights out-power off-refrigerator not working -temperature will rise-milk will sour. In other words, we diagnose (判定)a succession of effects from the power failure, each becoming the cause of the next.