请教LSAT-2-IV-16,21,23

mindfree

如果E中有唯一的话,没错. He is characterized by his big mouth. 能说明他没有鼻子和眼睛吗?

joywzy

以下是引用mindfree在2003-5-8 23:45:00的发言：
如果E中有唯一的话,没错.

能否说得详细点？怎么样改，E也成立？

谢谢。

albert

哦。。明白了。
如果说large amount of heat 是产生反应的唯一标准，则E正确。。
现在只是说 large amount of heat 是产生反应的一个character，而原文没有提到large amount of heat.所以不正确。。

mindfree, 通过你的分析，对逻辑清楚不少。。原来只求第一反应，懒得深咎其他答案，所以老是犯同样的错误，结果always feel frustrated...现在我对逻辑越来越有兴趣了。。
万分感谢。。

joywzy

啊，我对削弱中的所谓他因的干扰项有点明白了。

双鱼游

24题 This question asks us to weaken the argument. Recall: To weaken an argument, we typically must
attack a premise—either expressed or suppressed—of the argument. Now the underlying premise of any
controlled experiment is that there are no outside variables affecting its outcome. Two variables that come
immediately to mind are 1) there may be another source for the helium-4, and 2) helium-4 may be naturally
occurring in air. Now if the amount of helium-4 in the air after the experiment is the same as before the
experiment, then clearly the researchers’ claim would be spurious. Hence the answer is (C).