未讨论过的GWD31-Q17。我就想知道我是不是理解错题意了？？

刷牙不起沫

17. GWD31-Q17 B
It is crucially important to farmers that the herbicides they use to control weeds not damage their crops. One very effective herbicide is safe for corn, but soybeans are damaged even by the herbicide’s residue, which remains in the soil more than a year after the herbicide is applied. Soybeans and corn are not sown together in the same filed; nevertheless, most farmers are reluctant to use the herbicide on their corn.
Which of the following, if true, provides the strongest justification for the farmers’ reluctance?

A.    ! The residue of the herbicide in the soil a year after application is not enough to control most weeds effectively.
B.    To maintain the nutrients in the soil, corn and soybeans are often planted in a field in alternate years.
C.    The demand for soybeans is growing faster than is the demand for corn.
D.    For maximum yield, soybean plants are grown closer together to each other than are corn plants.
E.    The application of herbicides is less critical for soybean than for corn crops.

我理解题目问的是农民们为什么会犹豫，于是我选了C。但答案是B.如果是B的话，意思是如何能使农民不那么犹豫？？

2008115061

楼主的想法我猜是这样的：为什么农民不肯用herbicide? 因为这玩意会伤害soybean，而soybean现在受欢迎，所以不要使用。 想法其实也make sense, 但LZ的思维方式现在不是GMAC想看到的- -（我直说了哈，见谅）
but soybeans are damaged even by the herbicide’s residue, which remains in the soil more than a year after the herbicide is applied
这句话看看清楚，一切的推理就应该从这里发起。B说明了soybean和crop在种植上是有时间差的，所以这个时间差会让herbicide危害到crop.

chenchel

Because the question stem only states the soy and corn could not be planted together and from the question stem, it can be implied that the farmers do not want to use the herbicide because they want to plant the two together, or alternatively. So need to look for the reason why they want to plant the two plants together or alternatively.

janelee19

我选了D。为什么D不对呢

ruilin要出国

楼主的想法我猜是这样的：为什么农民不肯用herbicide? 因为这玩意会伤害soybean，而soybean现在受欢迎，所以不要使用。 想法其实也make sense, 但LZ的思维方式现在不是GMAC想看到的- -（我直说了哈，见谅）
but soybeans are damaged even by the herbicide’s residue, which remains in the soil more than a year after the herbicide is applied
这句话看看清楚，一切的推理就应该从这里发起。B说明了soybean和crop在种植上是有时间差的，所以这个时间差会让herbicide危害到crop.

-- by 会员 2008115061 (2010/8/14 0:08:13)

我开始选的也是C，但后来理解时发现，农民犹豫的是用不用H与CORN有关，加入像C答案中是因为S的需求大于C，那与用不用H也没有直接的关系，或许有其他更好的H之类的呢，增加了无关的变量。所以我的理解是：
因为要保持土地的营养，C和S需要交替的种，但是如果用H除草的话就会因为S被damaged而影响C，所以农民选择不用H。

艾瑞嘻同学

这道题是典型的fill the gap。C虽然看起来很attempting, 但是按照原文的条件，因为soybean 和 corn不被种在一个field而且soybean的demand很高，那农民完全可以在种soybean的field里面扩大soybean的种植啊，不需要考虑corn的heribicide这个因素。

那么要reason农民不用corn herbicide这个behavior, 必须附加一个条件去建立soybean,corn和corn herbicide之间的联系。选项B很好得做到了这一点：因为corn和soybean是在一个field里面年复一年交替种植的，所以corn herbicide的residue是会影响到soybean的。

zincgirl

谢谢讨论，做对了但看的答案错了，误导了一阵子！