GMAT语法比较与比较省略的知识点介绍.

GMAT考试语法部分考生一般准备的时间比较多，我们知道在GMAT语法中有很多知识点是我们熟悉的，当然也有很多知识点是比较陌生的。比如比较的用法，比较省略需要注意什么?澳际小编下面就分享一些GMAT考试技巧，希望大家都能掌握：

　　1. 比较中的省略

　　① 省略的名词，其单复数必须一致。如果单复数不一致，需要补出名词。

　　Her company did better last year than [those] of her competitors. 错，Those无指代。

　　Her company did better last year than [the companies] of her competitors. 对

　　② 省略的内容，可以是动词、单位、整个句子。

　　I walk fater than James [walks].

　　Whereas I drink 2 quarters of milk a day, my friend drinks 3 [quaters].

　　I walk as fast now as [I walked] when I was a child.

　　③ 状语比较的时候，可以省略than后面整个主句，不管时态是否一致。

　　例如上面的句子，I walk 与 I walked时态不一致，但是都省略了，比较的重点是时间——now和when I was a child

　　④时间状语的比较，能否省略取决于than前面是否有相应的时间状语。有的话，than后面主句可以省略;没有的话，than后面需要补出主谓，以避免比较对象上的歧义。

　　To develop more accurate population forecasts, demographers would have to know a great deal more than(they do) now about the social and economic determinants of fertility.

　　[they do]不能省略，因为than前面没有相应的状语结构

　　A large rise in the number of housing starts in the coming year should boost new construction dollars by several billion dollars, making the construction industry’s economic health much more robust than (it was) five years ago.

　　[it was]不能省略，因为than前面没有相应的状语结构

　　Soaring television costs accounted for more than half the spending in the presidential campaign of 1992, a greater proportion than in any previous election.

　　[in any previous election]前面没有补出[that]，因为than前面有1992与in any previous year相对应。

　　⑤完整主谓宾结构是被动语态的时候，状语比较，省略的通常还是than后面整个句子(与主动语态相同处理)，如果不采用省略结构，通常是【主语+补出助动词be】。如果仅补出be后面的done而省略Be，要看后面是否存在语义上的歧义。

　　例1：【In Japan】 elderly people are treated with far GREATER respect THAN they are 【in most Western countries】

　　例2：According to public health officials, in 1998 Massachusetts became the first state in which more babies were born to women【over the age of thirty】 than【under it】. 仅补出born，会产生under it修饰born的歧义。

　　例3：In no other historical sighting did Halley&aposs Comet cause such a worldwide sensation as in its return of 1910–1911.

　　2.比较中的指代——“that” or “it”

　　①That/those表示“同类指代”，也就是“核心词指代”，只指代“核心名词”，不带名词的修饰成分。

　　That/those后面通常在加上其他成分，表明与前面名词的不同。

　　②It/they表示“同物指代”，指代的名词就是前面加了一堆限定的名词。

　　出现it/they一定是自己跟自己比，要么是时间上的不同，要么是空间上的差异。

　　【In Japan】 elderly people are treated with far GREATER respect THAN they are 【in most Western countries】

　　They指代elderly people，老年人与老年人比，比较的是【in Japan】和【in most Western countries】

　　③在than或as后面补出的如果是it/they/I/he/...等，表示同一事物的比较时候，than后面的主语是可以省略的(连同谓语)。

　　I walk as fast now as [I walked] when I was a child.

　　还有一种特殊情况：those/it指代“核心词”，虽然不是同一个事物，但是than后面也可以省略(可能还会连同其他成分)。关键是要明确比较的重点。

　　例1. According to public health officials, in 1998 Massachusetts became the first state in which more babies were born to women【over the age of thirty】 than【under it】.

　　Than后面省略了those born to women

　　例2. Only seven people this century have been killed by the great white shark, the man-eater of the movies—fewer than [have been killed by bee stings].

　　Mia最初认为，than后面省略了those(指代people)。

　　但是有理解说，这里比较的并不仅仅是only seven people，后面的have been killed也在比较范围之内。所以不能是fewer than those killed by bee stings，因为这样就变成了seven people 和“被蜜蜂杀死的人”的比较。

　　Mia同意上述观点。

　　这里应该补出完整的比较：

　　Only seven people this century have been killed by the great white shark, fewer than [people have been killed by bee stings].但是这种说法是不符合语法规则的。Than后面不能在加上一个句子。

　　所以，这时候的省略就是必须的!

　　例3. According to recent studies comparing the nutritional value of meat from wild animals and meat from domesticated animals, wild animals have less total fat than [that of] livestock fed on grain and more of a kind of fat thought to be good for cardiac health.

　　That of不能省略，因为比较的是fat。

　　例4. In addition to having more protein than wheat does, rice has protein of higher [quality] than [that] in wheat, with more of the amino acids essential to the human diet.

　　That指代protein，不能省略。也可以这么说：

　　[Rice] has protein of higher quality than [wheat] does

　　3. 比较中助动词的补出

　　助动词的补出都出现在主语比较中，为了避免比较上的歧义。

　　补出的助动词：be/ do/ did/ have/ 情态动词

　　具体补出什么，取决于than/as前面句子的动词——be补be，实意动词补do/did/does，完成时态补have/ had/ has，情态动词补情态动词。

　　注意：

　　主谓结构或主系表结构，主语比较一般是不需要补出助动词的，但是补出了也不一定错。但是，如果than/as后面事态发生变化，一定要补出助动词!

　　一个比较特殊的题：

　　2-96 There are hopul signs that we are shifting away from our heavy reliance on fossil fuels: more than ten times as much energy is generated through wind power now than it was in 1990.

　　(A) generated through wind power now than it was

　　(B) generated through wind power now as it was

　　(C) generated through wind power now as was the case

　　(D) now generated through wind power as it was

　　(E) now generated through wind power than was the case

　　key: C

　　这个题目因为时态的转变必须补出was;其次比较对象是整句话的属性，而不仅仅是energy，所以不用that来补出，但是却又不能用it来指代主语，所以就只能用as was the case了。

　　总之，关于比较和比较中的省略，说难也不难。

　　关键点：如果省略能使比较更清晰就省略;如果省略会带来比较上的歧义，一定不要省。

　　省略的一定不是比较的重点，省略是为了更好地突出比较的重点。

　　实战中，还要看比较中省略的部分会不会带来语义上和逻辑上的歧义。

　　以上就是小编整理的GMAT考试语法部分考生要关注的重点知识，关于比较的使用方法一直是GMAT语法比较重要的部分。所以希望大家多去掌握一些GMAT考试技巧，这样我们的复习才会更加的顺利。