句子改错题(Sentence Correction)主要测试考生应用语言，特别是标准书面英语的能力。它不仅要求一句话在语法和句法上完全正确，而且要求这个句子简明扼要，而非含混不清，即逻辑表达的简洁性、逻辑意思的合理性和单一性的统一。GMAT句子改错题干中所给的句子一般都比较复杂，较多使用从句。我们选择答案的原则是要使得句子尽量完整、明确、有效，而且要简洁，其中简洁这一原则很容易造成我们在做题时选择那些省略从句连接词的选项，但是GMAT在从句这方面是十分严谨的，所以还是要选择能够把意思表达完整、带有连接词的选项，有些考生误把这当成解题的一个制胜法宝，见到这样的句子就带上连接词一定就不会错了吗?No!有些句子在加入连接词后虽然句意变得非常完整，但改写后的句子很拗口、重复，这显然违背了简洁的原则，所以我们的思维就不能只限制在这一个单一句型上了，用其他方式来改写从句，使之后变得简洁而又不失完整性不是更好吗?一起来看看以下几个例子吧：
Sartre believed each individual is responsible to choose one course of action over another one, that it is the choice that gives value to the act, and that nothing that is not acted upon has value.
(A) Each individual is responsible to choose one course of action over another one
(B) That each individual is responsible for choosing one course of action over another
(C) That each individual is responsible, choosing one course of action over another
(D) That each individual is responsible to choose one course of action over another
(E) Each individual is responsible for choosing one course of action over other ones
本题的划线部分是一个宾语从句，看到这大家会首先想到GMAT的死原则：宾语从句中的连接词that 不能省略，而且纵观几个选项都是采用了宾语从句的表达方法，所以我们就可以放心大胆地排除掉A和E答案，然后再从其他方面进行比较分析。下面这个例子是说明满足简洁原则的情况：
Gall’s hypothesis of there being different mental functions localized in different parts of the brain is widely accepted today.
(A) Of there being different mental functions localized in different parts of the brain is widely accepted today
(B) Of different mental functions that are localized in different parts of the brain is widely accepted today
(C) That different mental functions are localized in different parts of the brain is widely accepted today
(D) Which are that there are different mental functions localized in different parts of the brain is widely accepted today
(E) Which is widely accepted today is that there are different mental functions localized in different parts of the brain
D答案中的which is that 表达不简洁，必须省略which is，直接用that 引导同位语从句，而且省略掉which is 的句子依然完整明确。以上两个例子都是比较明显的究竟是满足完整还是简洁的情形，迷惑性不大，下面这个例子就相对复杂一些：
A controversial figure throughout most of his public life， the Black leader Marcus Garvey advocated that some Blacks return to Africa， the land that， to him， symbolized the possibility of freedom。
(A)that some Blacks return to Africa， the land that，to him， symbolized the possibility of freedom
(B)that some Blacks return to the African land symbolizing the possibility of freedom to him
(C)that some Blacks return to Africa which was the land which symbolized the possibility of freedom to him
(D)some Black's returning to Africa which was the land that to him symbolized the possibility of freedom
(E)some Black's return to the land symbolizing the possibility of freedom to him，Africa
本题的正确答案为A，即采用了题干中所给的用法。许多考生很容易选择D，理由是根据GMAT语法的一般要求，不省略从句连接词从而保证句子的完整性D答案从语法上看没什么错误，但是这种表达方式连用了两个定语从句，显得重复罗嗦，很不简洁，读起来也不顺畅。A选项是采用同位结构的方式，看起来更简洁一些。
GMAT语法要求我们不省略从句连接词，从而使得句意完整明确，但罗嗦繁杂的句子又是非常忌讳的，同时也不符合英语的习惯表达。所以在句子完整明确的基础上，我们不能忽略语言表达习惯以及句子的简洁性，简洁不是随意进行省略，它必须建立在符合GMAT要求逻辑关系的基础之上。要力求使自己的思维不受从句的束缚，如果有比从句简洁的表达方式，当然会成为我们的首选。