1.Downzoning, zoning that typically results in the reduction of housing density, allows for more open space in areas where little water or services exist.
(A) little water or services exist
(B) little water or services exists
(C) few services and little water exists
(D) there is little water or services available
(E) there are few services and little available water
这是一道典型的难题，充分体现了GMAT语法中的相对正确性的原则。A选项中little这个词既修饰了water又修饰了services，但是little只能修饰不可数名词，所以它只能修饰water而不能修饰services, 所以A选项语法是不对的，而这是个正确性的错误。同样B和D都犯了类似的错误。C选项中主语few services and little water是复数，而谓语却是单数，也错了。E选项其实也有错，首先用了there be的句型，这在GMAT语法中一般是不允许的，其次又加了available这个词，把原文的意思也改变了，但这些错误从性质上来看只是有效性的错误，起码它语法是正确的，而A，B，C，D语法都错了，所以答案选E。
我们再看一道非常类似GMAT语法中的相对正确性的题目：
2.The commission acknowledged that no amount of money or staff members can ensure the safety of people who live in the vicinity of a nuclear plant, but it approved the installation because it believed that all reasonable precautions had been taken。
(A) no amount of money or staff members
(B) neither vast amounts of money nor staff members
(C) neither vast amounts of money nor numbers of staff members
(D) neither vast amounts of money nor a large staff
(E) no matter how large the staff or how vast the amount of money
这道题目和刚才那题非常类似，amount of 这个短语可以修饰不可数名词但不能修饰可数名词，而A和B选项中amount of同时修饰了money这个不可数名词和staff members这个可数名词，所以都是错误选项。C选项中出现了numbers of，这是个错误的表达方式，表示某物的数量应该用the number of，所以也错了。E选项no matter how 罗嗦，首先用however会显得更为简洁，而其实即使改用however还是错，因为这是个强烈语气表达，原文中没有使用正确答案就不能使用。答案选D，有些凭语感解题的同学会觉得D选项看上去很不顺眼，但解GMAT语法题千万不能凭语感，而要靠扎扎实实的语法分析。A，B，C，E都存在着一定程度的错误，所以答案选D。