OG10-200实在参悟不了，望牛牛们指点

honeypony

200.Certain pesticides can become ineffective if used repeatedly in the same place: one reason is suggested by the finding that there are much larger populations of pesticide-degrading microbes in soils with a relatively long history of pesticide use than in soils that are free of such chemicals.
(A) Certain pesticides can become ineffective if used repeatedly in the same place; one reason is suggested by the finding that there are much larger populations of pesticide-degrading microbes in soils with a relatively long history of pesticide use than in soils that are free of such chemicals.
(B) If used repeatedly in the same place, one reason that certain pesticides can become ineffective is suggested by the finding that there are much larger populations of pesticide-degrading microbes in soils with a relatively long history of pesticide use than in soils that are free of such chemicals.
(C) If used repeatedly in the same place, one reason certain pesticides can become ineffective is suggested by the finding that much larger populations of pesticide-degrading microbes are found in soils with a relatively long history of pesticide use than those that are free of such chemicals.
(D) The finding that there are much larger populations of pesticide-degrading microbes in soils with a relatively long history of pesticide use than in soils that are free of such chemicals is suggestive of one reason, if used repeatedly in the same place, certain pesticides can become ineffective.（A）
(E) The finding of much larger populations of pesticide-degrading microbes in soils with a relatively long history of pesticide use than in those that are free of such chemicals suggests one reason certain pesticides can become ineffective if used repeatedly in the same place.

其中（1）不明白D项的句子结构，只知道The finding that ... is suggestive, if used repeatedly in the same place, certain pesticides can ...是句子主干，但句子意思和结构不明白，关键看不懂if 的链接作用

（2）不明白，the phrase if used repeatedly in the same place illogically modifies one reason rather than certain pesticides.（摘自OG10的注解）即为什么if 从句修饰one reason ？

thinkingape

D有两处问题：
1、finding is suggestive of one reason，这种表达结构太那什么了，finding suggests one reason要简洁的多。GMAT里，能用动词就不要用形容词，过于罗嗦了。
2、前后两个句子用逗号连接，这个也是明显的错误

你的第二个问题：
其实你可以这样理解，第一句讲了什么是one reason，而if 从句是对one reason的具体说明，这个原因是什么呢，就就if从句的内容。

GMAT里面有个原则，同位语结构修饰与其位置最近的名词

honeypony

先谢谢楼上的回复。
我谈一下自己的体会：
D项：The finding is suggestive of one reason, if used repeatedly in the same place, certain pesticides can become ineffective.这是句子主干，但有问题的是if 引导的从句没有办法做同位语修饰reason,因为只有that能引导同位语，但为什么OG的解释是the phrase if used repeatedly in the same place illogically modifies one reason rather than certain pesticides.
在我看来，if 从句本身就不可能去修饰reason这是语法上的错误，但为什么OG却把它定位成修饰关系上的错误，求大牛指导！

arthurman

理清一下，OG的解释引用的是If used repeatedly错误修饰reason。 used

修饰紧跟其前的名词reason即 if (the reason) used repeatedly... 逻辑错

误， 只能是if (pesticides) used repeatedly

本题首先排除BC,  one reason做前面used的逻辑主语错误
D项同样的逻辑修饰错误+ suggestive不简洁
E The finding of ....全句awkward

yangmbalin

状语从句只能修饰动词，形容词。在这里，是状语从句的省略形式，省略了主语The finding，也就是说的逻辑主语。你还原句子The finding repeatedly.........就会发现是没有逻辑的。从这个角度，D错。

honeypony

谢谢楼上牛牛们的回复，大家指出的错误地方我也能看明白，但实在不明

白D项句子的链接if从句怎么可能修饰one reason,就因为紧跟在reason后？？

我个人认为D项错误原因是reason和if之间缺乏连接词使得后面的if从句修饰

reason而不像OG说的OG的解释是the phrase if used repeatedly in the same

place illogically modifies one reason rather than certain pesticides.,求指导