GMAT语法题，又称句子改错题(sentence correction)，是整个GMAT考试中对考生英语语法能力考查要求最高的题型，也往往是中国学生最为头疼的一类题目。没有扎实的语法基础和一定的逻辑分析能力，想要做好语法题难度极高。怎样做好GMAT语法题?下面小编就通过一些经典真题的实例解析，为大家全面讲解GMAT语法题的解题思路和方法技巧。
实例题目：
In a review of 2,000 studies of human behavior that date back to the 1940s, two Swiss psychologists, declaring that since most of the studies had failed to control for such variables as social class and family size, none could be taken seriously.
(A) psychologists, declaring that since most of the studies had failed to control for such variables as social class and family size,
(B) psychologists, declaring that most of the studies failed in not controlling for such variables like social class and family size, and
(C) psychologists declared that since most of the studies, having failed to control for such variables as social class and family size,
(D) psychologists declared that since most of the studies fail in controlling for such variables like social class and family size,
(E) psychologists declared that since most of the studies had failed to control for variables such as social class and family size,
选项分析：
(A)psychologists, declaring that since most of the studies had failed to control for such variables as social class and family size,
【错误】 句子结构：本选项中“declaring”不能单独做谓语动词，于是“two Swiss psychologists”在主句中失去了谓语动词，主谓结构不完整。
(B)psychologists, declaring that most of the studies failed in not controlling for such variables like social class and family size, and
【错误1】 句子结构：见(A)。
【错误2】 固定搭配：“like”在标准书面英语中可以表示名词之间的相似性，不可以用于举例，“like”、“such like”用于举例是必错搭配。
(C)psychologists declared that since most of the studies, having failed to control for such variables as social class and family size,
【错误】 句子结构：“declared that”的后方应连接一个从句，这个从句中主语应该是“most of the studies”， “having failed”本应是其谓语动词，但语法上无法实现，因此“most of the studies”失去了谓语动词，主谓结构不完整。
(D)psychologists declared that since most of the studies fail in controlling for such variables like social class and family size,
【错误1】 动词时态：不同动词之间的时态差异需要合理解释，“declared是过去式而“fail”是一般现在时，此差异不存在合理解释。
【错误2】 固定搭配：见(B)中【错误2】。
(E)psychologists declared that since most of the studies had failed to control for variables such as social class and family size,
【正确】 “psychologists declared”构成主句的主谓结构，“that”引导从句，从句的主谓结构是“none could be taken seriously”，而“since most of the studies had failed to control for variables such as social class and family size”是从句的原因状语从句
【大意】 心理学家宣称，因为大多数研究无法控制如社会等级和家庭大小等变量，没有研究能被严肃对待。
解题思路：
(B)和(D)使用了错误搭配，立即排除。
(A)与(C)句子结构错误，立即排除。
因此选择(E)。
