section 1-10 10.Climatic shifts are so gradual as to be indistinguishable at first from ordinary fluctuations in the weather. (A) so gradual as to be indistinguishable (B) so gradual they can be indistinguishable (C) so gradual that they are unable to be distinguished (D) gradual enough not to be distinguishable (E) gradual enough so that one cannot distinguish them
答案为A，这点是肯定的，因为BCDE都不对（B中so后面没有对应that或是as; C是典型的be able to be done的错误; D和E用了enough，直接咔嚓~） 这里的正确选项A用了so...as to的结构，记得OG12-37里的C的解释说so...as to...不是正确的结构：
37. Although schistosomiasis is not often fatal, it is so debilitating that it has become an economic drain on many developing countries. (A) it is so debilitating that it has become an economic (B) it is of such debilitation, it has become an economical (C) so debilitating is it as to become an economic (D) such is its debilitation, it becomes an economical (E) there is so much debilitation that it has become an economical
C The construction so x as to y is not a correct idiom.
这个C里用了倒装使结构变得awkward，如果改为it is so debilitating as to become...时态又有问题，应该用完成时更恰当。但是撇开这些问题，单单看it is so debilitating as to become这个结构，不知道是正确还是错误呢？查过以前关于这个结构的很多讨论贴，如 http://forum.chasedream.com/GMAT_SC/thread-402706-2-1.html 里说到GMAC认为“so as to“必须连用，而”so...as to"的结构是错误的。这和本人刚开始做OG的印象是一致的，但这又和上面大全里的那题有冲突。上新东方的时候，记得老师讲过so...as to的表达最为简洁，但是这个结构要求很高，要求逻辑主语一致和时态一致。
实在是很晕，大家来讨论下啊~作者: sunfish223 时间: 2010-5-3 12:46
同问这个问题 @@作者: tracy沁 时间: 2010-5-3 19:44
我实在是菜鸟，只是凭感觉来的。 根据白勇语法上的说法来看so as to 和so ···as to 都可以。但都只能用于单一主谓结构中逻辑主语等于句子主语，即句子主语必须可以执行as to后的动词所表达的动作才对，否则错。并且“so ···as to结构不能用于倒装语序”。 这是完全摘自白勇语法书上的。作者: Jessielynn 时间: 2010-5-5 20:22
嗯~楼上的说法蛮有道理的~
继续up~作者: bonnie0715 时间: 2010-5-5 21:01
so as to不能连载一起用，一定要说A is so ....as to ...不能说S is ...so as to.作者: anythink 时间: 2010-7-18 02:46
37题这里有is it的出现，所以不能用as to作者: 红尘道士 时间: 2010-7-18 08:47
我感觉it is so debilitating as to become也是正确的，不一定非要用完成时作者: olivertang 时间: 2010-9-8 08:35
但是白勇P246页38题中的E选项：these drugs caused such sever stomach disorders as to be banned by food and drug adminstration为什么不对呀？
比较这个正确的：Climatic shifts are so gradual as to be indistinguishable at first from ordinary...