GMAT语法改错的一个独特之处在于A选项与题干划线部分完全一样，也就是说划线句既是题干又可能是答案，较之传统题型有很大区别，因为我们已经习惯了从传统语法改错给定的划线部分挑毛病或完全认定划线句的合理性，从而对其进行理解和分析。划线句在给考生提示的同时又在制造干扰，我们在解题过程中要遵循划线句而又不能受制于它，应付起来并不容易。GMAT语法改错的考查要点主要集中在句子结构、惯用搭配、逻辑关系、动词形式几个方面，在对划线句不肯定也不否定的前提下，这几方面基本上也都是待定的，所以在解决语法改错题时利用排除法显得至关重要，合理的方法是在划线句中寻找语意之类的大体信息，从未划线部分寻找提示，做到心中有数，然后反复比较选项间的差异，确定出最终答案。考生可以通过以下几个例子仔细体会一下。 1. For all his professed disdain of such activities, Aden was an inveterate literary gossip. （A）For all his professed disdain of such activities （B）Having always professed disdain for such activities （C）All such activities were，he professed disdained and （D）Professing that all such activities were disdained （E）In spite of professions of disdaining all such activities 本题的划线句成分比较简单，所考查的要点为for的使用和profess，disdain两个动词与未划线句的对应。B、C、D、E四个选项都将profess作为主语发出的动作，分别用四种不同句型表达，如果主语发出的动作重心在profess上，那么这句话的逻辑关系就出了问题，句子不通。排除掉四个选项之后，正确答案只剩A。如果能判断到profess和disdain两个动词究竟哪个与主语对应这个层面上，其他四个选项就可以作为一个整体进行排除。 2. The department defines a private passenger vehicle as one registered to an individual with a gross weight of less than 8,000 pounds. (A) As one registered to an individual with a gross weight of less than 8,000 pounds． (B) To be one that is registered to an individual with a gross weight of less than 8,000 pounds. (C) As one that is registered to an individual and that has a gross weight of less than 8,000 pounds. (D) To have a gross weight less than 8,000 pounds and being registered to an individual (E) As having a gross weight of less than 8,000 pounds and registered to an individual 本题的划线句语法错误是比较明显的，只要牢记GMAT语法的一个原则：不省略从句引导词，就能迅速判断出正确答案为C。本题还考查了define as这样一个固定搭配。其实如果语感比较强的话在读划线句的时候就已经产生怀疑了，但先不要急着下结论，依旧要从五个选项中进行排除，本题不需要再从未划线部分寻找其他关于逻辑关系之类的提示。 3. Added to the increase in hourly wages requested last July, the railroad employees are now seeking an expanded program of retirement benefits. （A）Added to the increase in hourly wages requested last July，the railroad employee are now seeking an expanded program of retirement benefits． （B）Added to increase in hourly wages which had been requested last July，the employees of the railroad are now seeking an expanded program of retirement benefits. （C）The railroad employees are now seeking an expanded program of retirement benefits added to the increase in hourly wages that were requested last July. （D）In addition to the increase in hourly wages that were requested last July, the railroad employees retirement benefits. （E）In addition to the increase in hourly wages requested last July, the employees of the railroad are now seeking an expanded program of retirement benefits. 这道题目比较特别，划线句是全部的题干，这无疑增加了难度，可能是前半句有问题，也可能是后半句，或者都有问题抑或正确答案就是A。Added to这种用法并不常见，所以前半句有问题的可能性很大，通过使用排除法可以确定正确答案为E。注意E中的修饰wages的从句引导词被省略了，但是这是相比之下的最合适的答案了，如果还有一个答案是没有省略引导词的，我们还是要选择后者。 由此可见，我们对待GMAT语法改错划线句没有一个统一的方法而言，而要结合未划线部分和其余四个选项从多方进行比较、推敲来确定最合适的那一个。 | 
