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：
Digging in sediments in northern China, evidence has been gathered by scientists suggesting that complex life-forms emerged much earlier than they had previously thought.
(A) evidence has been gathered by scientists suggesting that complex life-forms emerged much earlier than they had
(B) evidence gathered by scientists suggests a much earlier emergence of complex life-forms than had been
(C) scientists have gathered evidence suggesting that complex life-forms emerged much earlier than
(D) scientists have gathered evidence that suggests a much earlier emergence of complex life-forms than that which was
(E) scientists have gathered evidence which suggests a much earlier emergence of complex life-forms than that
选项分析：
(A)evidence has been gathered by scientists suggesting that complex life-forms emerged much earlier than they had
【错误】 修饰成分：“Digging in sediments in northern China”应当是“scientists”发出的动作，但根据语法要求，它必须是其后跟随的主谓结构“evidence has been gathered”的状语，修饰的是“has been gathered”，逻辑主语是“evidence”，语义明显不合理。
(B)evidence gathered by scientists suggests a much earlier emergence of complex life-forms than had been
【错误】 修饰成分：见(A)。
(C)scientists have gathered evidence suggesting that complex life-forms emerged much earlier than
【正确】 “that”引导的从句“complex life-forms emerged much earlier than previously thought”是“suggesting”的宾语，准确叙述了“evidence”的具体内容。
【大意】 在北中国挖掘沉积物的时候，科学家发现了证据暗示着复杂生命形式出现得比之前认为的还早。
(D)scientists have gathered evidence that suggests a much earlier emergence of complex life-forms than that which was
【错误1】 句子意思：“evidence”暗示的内容应是“复杂生命形式出现的比之前认为的更早”，而不是“emergence”本身，因此(D)表意逊于(C)使用“complex life-forms emerged much earlier than previously thought”。
【错误2】 固定搭配：不存在用“which”引导的定语从句修饰代词“that”的用法。
(E)scientists have gathered evidence which suggests a much earlier emergence of complex life-forms than that
【错误】 句子意思：见(D)中。【错误1】
解题思路：
“evidence”无法发出“digging”的动作，立即排除(A)、(B)，科学家收集到的证据暗示的是“复杂生命形式出现的比之前认为的更早”这件事，既然是一件事，那么用主谓结构表述语义更加，(C)优于(D)、(E)，因此选择(C)。
