这道题实在想不通B错在哪里，请大家帮忙把我从牛角尖里拉出来吧，先谢谢了

icerach

Plantings of cotton bioengineered to produce its own insecticide against bollworms, a major cause of crop failure, sustained little bollworm damage until this year. This year the plantings are seriously damaged by bollworms. Bollworms, however, are not necessarily developing resistance to the cotton’s insecticide. Bollworms breeds on corn, and last year more corn than usual was planted throughout cotton-growing regions. So it is likely that the cotton is simply being overwhelmed by corn-bred bollworms.

In evaluating the argument, which of the following would it be most useful to establish?

A. Whether corn could be bioengineered to produce the insecticide

B. Whether plantings of cotton that does not produce the insecticide are suffering unusually extensive damage from bollworms this year

C. Whether other crops that have been bioengineered to produce their own insecticide successfully resist the pests against which the insecticide was to protect them

D. Whether plantings of bioengineered cotton are frequently damaged by insect pests other than bollworms.

E. Whether there are insecticide that can be used against bollworms that have developed resistance to the insecticide produced by the bioengineered cotton.

答案是D，可是，我实在不知道B错在哪里，因为原文都说了“This year the plantings are seriously damaged by bollworms. ”，这可以认为是一个事实么？

我当初的考虑：
B选项：Whether plantings of cotton that does not produce the insecticide are suffering unusually extensive damage from bollworms this year

取非：如果未经生物工程的cotton没有遭受非同寻常的虫害，说明并不是因为虫多，也就不存在overwhelmed by BW了。削弱结论。

如果取正，未经生物工程的cotton也同样遭受了不一般的BW虫害，则支持结论。

我的思路是把经过生物工程和未经生物工程的cotton看作两个对照组来考虑的，类似于实验类题目的思路。。

howardwang

MM

结论是So it is likely that the cotton is simply being overwhelmed by corn-bred bollworms.

仔细理解一下结论，然后，将D取非和不取非，则你就知道自己错在那里了。

icerach

howard，

我想，B的错误是否是在对B取非，对结论构成削弱，但是对B取正，却不一定加强，B的描述如果改成Whether plantings of cotton that does not produce the insecticide are suffering unusually extensive damage from bollworms this year compared with last year可能会更好。

而D，取正对结论直接削弱，取非则加强。

其实，我是被原文中的细节给困扰了，因为原文中有一句话Plantings of cotton bioengineered to produce its own insecticide against bollworms, a major cause of crop failure, sustained little bollworm damage until this year. This year the plantings are seriously damaged by bollworms. Bollworms, however, are not necessarily developing resistance to the cotton’s insecticide. Bollworms breeds on corn, and last year more corn than usual was planted throughout cotton-growing regions. So it is likely that the cotton is simply being overwhelmed by corn-bred bollworms.

我把它看成了facts，所以一开始选择的时候把D就排除了。看来CR是不能拘泥于细节的。

谢谢howard不厌其烦的回答。

[此贴子已经被作者于2005-8-18 14:19:13编辑过]

howardwang

问题的结论是So it is likely that the cotton is simply being overwhelmed by corn-bred bollworms.

结论中，两个红色字体的词最关键。

所以，要支持，你就找选项为什么corn-bred bollworms是仅有的（simply）的......

要反对，你就找选项为什么corn-bred bollworms不是仅有的（simply）的......

MM记住阿，结论的具体性和特殊性之重要性怎么强调斗不过分的。

我觉得，B应该一看就排出的，它与评价结论的距离相去甚远。

[此贴子已经被作者于2005-8-18 16:38:58编辑过]

icerach

结论的具体性和特殊性之重要性怎么强调斗不过分的。

很受启发，谢谢。

又加深了一个印象，在解题的时候除了注意 line of reasoning 之外，还要对关键字保持敏感。

howardwang

怎么没谢谢GG。哈哈，开个玩笑。明白就好！

icerach

[此贴子已经被作者于2005-8-19 0:21:30编辑过]

leonchan

B只能说明 plantings of cotton that does not produce the insecticide 与虫害之间的关系，如4楼所说，不能影响 simply being overwhelmed by corn-bred bollworms

howardwang

以下是引用icerach在2005-8-19 0:14:00的发言：

也谢谢MM漂亮的鲜花！