一道逻辑题

rexue70UID: 3374501

我选的是第四个，为什么第三个对？

crazyrobinUID: 2368627

这道题你要先找core
conclusion: Increased development in suburban is the reason of DS's appearance.
Premise: urban development makes rain flows directly into streams and cause the decrease of organic sediment.

Gap?

1) could it be the case that DS actually is wiped out due to other factors? 完全有可能，这次要 strengthen,必须把其他 factors排除

2) could it be possible that DS can accommodate to increased flow and prey on other organic?
完全有可能，要 strengthen你必须把这个也排除

这道题是 Strengthen, 对于这种因果关系的strengthen有两种方法
1)明确指出这种因果就是唯一的因果，比如, data show that DS extinc after the suburban development，你觉得这个 strengthen了这个 argument了吗？ well a little bit, since it conforms with the argument that DS indeed disappears; 再比如, the increased flow washes away all the micro organic and food DS preys on. 这个明显 strengthe了这个argument.

2)排除其他可能，也就是并不是其它因素造成DS的消失

ABDE全部都 out of scope.
你注意这个core, core是 increased flow is the factor accounts for DS's extinction.
D讲了polution对 aquatic animal的影响， what about DS?
C刚好指出了 另外一种动物即可以在swift也可以在 slow streams里生长，从另外一个角度说明 swift streams可以造成DS extinction.

这题Strengthen还有另外一种方法，把D改编一下, the pollution in the suburban NY has increased significantly which endangers species in the habitas where DS lives, but study suggests that DS had a gene which can accimilate the poisonous pollution.

为什么这句话 strengthen了这个 argument,因为排除了其他可能。

Please let me know if you have any questions.

rexue70UID: 3374501

crazyrobin 发表于 2013-4-25 18:08
这道题你要先找core
conclusion: Increased development in suburban is the reason of DS's appearance.
...

太感谢了，讲解清晰明确，我顿时恍然大悟！

分析很严谨也很高级，但对于我的水平至少我明白了，如果strengthen连core的主语都没有提到那就肯定与题目无关了。真是麻烦版大费心了。

明天最后一天不打算学了。虽然单词3000第10遍没过完，但是也就这样了。数学做了陈向东，难句也尽力了。

再次感谢这么多的字帮助我！一路走来，听到cr说的话就好像心里吃了定心丸一样。明天就放松下好了。后天轻松上阵！感谢寄托，感谢CR。

crazyrobinUID: 2368627

rexue70 发表于 2013-4-25 21:05
太感谢了，讲解清晰明确，我顿时恍然大悟！

分析很严谨也很高级，但对于我的水平至少我明白了，如果 ...

Good luck!!祝你好运

siluhulianUID: 3426568