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.
是最近几天翻lawyer的老帖,才了解了一点充分条件和必要条件,但是好像还是不太会用。这个题目我觉得很典型,选项里充满了充分条件、必要条件的指示词,尝试分析如下,欢迎指正,一起探讨。
原文推理链如下: institutes new parking regulations —〉increase in parking violations—〉a greater number of parking fines collected—>city revenues will increase
A Unless there is an increase in the number of parking violations in the city, city revenues will not increase. 错误原因:推理链显示 an increase in the number of parking violations 是充分条件,而这里将原文的If 改成unless,变为必要条件。
B If the city council institutes new parking regulations, the council will fall from favor with the citizens. 错因:fall from favor with the citizens 是原文没有的新信息,排除。
C The city council will institute new parking regulations only if an increase in city revenues can be expected to result 疑惑:据推理链,an increase in city revenues can be expected to result 的确是必要条件啊,only if 后面接必要条件没有错啊。 但是根据“感觉”,又觉得此项说的和原为的意思有点出入。 所以我就不明白了,是听从感觉呢,还是依从方法,还是我分析充分必要的时候分析错了?请NN指教!
D If the city council’s new regulations cause more parking violators to be ticketed, the city revenues will increase. if 后的是充分条件,符合推理链。答案是原文某两句话的结合。
E Unless the city institutes a complex system of parking regulations, the city cannot expect traffic violations to increase 错因:同A。将if 换成unless,将原文的充分条件改为必要条件。
以上是我的分析和疑惑,请帮忙看看,这样分析对吗?需要这样地分析吗?C项的疑惑,该怎样解开呢?先谢谢了~~~
[此贴子已经被作者于2006-11-3 11:01:00编辑过] |