请教：”so as to"到底是不是一种正确的用法？急！

OG对“so ... as to”的评价是简单的not idiomatic (OG11 - 33 and 36). 但我不清楚OG是指在这一特定的语境中不好，还是根本这个结构就是错的。

OG33: (表结果)

Correct: Although schistosomiasis is not often fatal, it is so debilitating that it has become an economic drain on many developing countries.

Incorrect: Although schistosomiasis is not often fatal, so debilitating is it as to become an economic drain on many developing countries.

OG36:

Correct: In 1527 King Henry VIII sought to have his marriage to Queen Caterine annulled so that he could marry Anne Boleyn.

Incorrect: In 1527 King Henry VIII sought to have his marriage to Queen Catherine annulled so as to marry Anne Boleyn.

在Oxford dictionary里so ... as to 和so as to都是可以的用法。

so ... as to 表结果，表示到什么程度。例：I am not so stupid as to belive her.

so as to 表目的。例：We went early so as to get good seats.

在白勇的解释里，so as to的两种用法也是可以的，只要保证在单一主谓结构中避免歧义就可以了。

那么，到底ETS承不承认so as to这一结构呢?

各位有没有什么真题的例子里so as to是正确的？

关注~~

so...as to是正确的,但是没有到装的用法

so that和so as to主要是区别逻辑主语

可以搜索老贴,看看NN们的讨论~~

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

从主从句大并列的角度考虑：从句主系表，主句也应该主系表，而不用名词(什么东东并列, 就用什么东东)

这是我之前看的NN的总结
1，没见过so as to倒装
2，主要问题在于so as to的逻辑主语是谁不清楚。
千万注意：没有语法规则保证它的逻辑主语就是主句主语。所以，虽然从逻辑上说很容易想到它的主语就是主句主语，而且这样理解起来也非常自然，但在语法上是无法保证的，所以可能造成理解上的混乱。

这是我之前看的NN的总结
1，没见过so as to倒装
2，主要问题在于so as to的逻辑主语是谁不清楚。
千万注意：没有语法规则保证它的逻辑主语就是主句主语。所以，虽然从逻辑上说很容易想到它的主语就是主句主语，而且这样理解起来也非常自然，但在语法上是无法保证的，所以可能造成理解上的混乱。

so as to 和so that 的另一重要区别是:so that 中包含了时态,在这种情况下,不能用so as to 代替

楼主&gmathacker:对于【so as to】结构从OG11－33、36观察，似乎否定了，偶尔发现OG10－88又被11th删掉，越来越象不能用

的说，有没有人已经研究过prep新版（300+）发现可以用【so as to】，或者近期考过GMAT的前辈实战见过呀，给点线索的说！

88. The Emperor Augustus, it appears, commissioned an idealized sculpture portrait, the features of which are so unrealistic as to constitute what one scholar calls an "artificial face."

(A)  so unrealistic as to constitute

(B)  so unrealistic they constituted

(C)  so unrealistic that they have constituted

(D)  unrealistic enough so that they constitute

(E)   unrealistic enough so as to constitute

The verbs are and calls indicate that the sculpture is being viewed and judged in the present. Thus, neither the past tense verb constituted (in B) nor the present perfect verb have constituted (in C) is correct; both suggest that the statue's features once constituted an artificial face but no longer do so. Also, B would be better if that were inserted after so unrealistic, although the omission of that is not ungrammatical. Choices D and E use unidiomatic construc­tions with enough: unrealistic enough to constitute would be idiomatic, but the use of enough is imprecise and awkward in this context. Choice A, which uses the clear, concise, and idiomatic construction so unrealistic as to constitute, is best.

大家再留意一下，gmat-sucks大大破解的 prep-sc1有发现一个：

65.        (28041-!-item-!-188;#058&003495)

Developed by Pennsylvania's Palatine Germans about 1750, they made Conestoga wagons with high wheels capable of crossing rutted roads, muddy flats, and the nonroads of the prairie and they had a floor curved upward on either end so as to prevent cargo from shifting on steep grades.

(A) they made Conestoga wagons with high wheels capable of crossing rutted roads, muddy flats, and the nonroads of the prairie and they had a floor curved upward on either end so as to prevent

(B) they made Conestoga wagons, which had high wheels capable of crossing rutted roads, muddy flats, and the nonroads of the prairie, and floors curved upward on their ends so that they prevented

(C) Conestoga wagons, with high wheels capable of crossing rutted roads, muddy flats, and the nonroads of the prairie, and had a floor that was curved upward at both ends to prevent

(D) Conestoga wagons had high wheels capable of crossing rutted roads, muddy flats, and the nonroads of the prairie, and a floor that was curved upward at both ends to prevent

(E) Conestoga wagons had high wheels capable of crossing rutted roads, muddy flats, and the nonroads of the prairie and floors curving upward at their ends so that it prevented

答案是（D）

A答案的so as to没有错啊, so as to可以简单看成to表目的.