GMAT语法考试中的一种超难题型——独立主格结构题型

GMAT语法考试中的一种超难题型——独立主格结构题型
文：夏鑫

GMAT考试中如果遇到独立主格结构这种类型，就一定是属于难度系数很高的题型，独立主格结构我们一般在写作中很少会用，但是看到这种句子，大家基本都能看懂，但是一旦到GMAT考试中，如何辨别，就很困难，怎么选择也是难点。

在讲独立主格结构之前。
下面来看看这样几道GMAT考试题，让我们对独立主格结构找点感觉：

1. Scientists have observed large concentrations of heavy-metal deposits in the upper twenty centimeters of Baltic Sea sediments, which are consistent with the growth of industrial activity there.
A. Baltic Sea sediments, which are consistent with the growth of industrial activity there
B. Baltic Sea sediments, where the growth of industrial activity is consistent with these findings
C. Baltic Sea sediments, findings consistent with its growth of industrial activity
D. sediments from the Baltic Sea, findings consistent with the growth of industrial activity in the area
E. sediments from the Baltic Sea, consistent with the growth of industrial activity there
这道题应该选D

2. Floating in the waters of the equatorial Pacific, an array of buoys collects and transmits data on long-term interactions between the ocean and the atmosphere, interactions that affect global climate.
A. atmosphere, interactions that affect
B. atmosphere, with interactions affecting
C. atmosphere that affects
D. atmosphere that is affecting
E. atmosphere as affects
这道题应该选A

3. Sixty-five million years ago, according to some scientists, an asteroid bigger than Mount Everest slammed into North America, which, causing plant and animal extinctions, marks the end of the geologic era known as the Cretaceous Period.
A. which, causing plant and animal extinctions, marks
B. which caused the plant and animal extinctions marking
C. and causing plant and animal extinctions that mark
D. an event that caused plant and animal extinctions, and it marks
E. an event that caused the plant and animal extinctions that mark
这道题应该选E

4. Sound can travel through water for enormous distances, prevented from dissipating its acoustic energy as a result of boundaries in the ocean created by water layers of
different temperatures and densities.
A. prevented from dissipating its acoustic energy as a result of
B. prevented from having its acoustic energy dissipated by
C. its acoustic energy prevented from dissipating by
D.its acoustic energy prevented from being dissipated as a result of
E. preventing its acoustic energy from dissipating by
这道题应该选C

5. For protection from the summer sun, the Mojave lived in open-sided, flat-topped dwellings known as shades, each a roof of poles and arrowweed supported by posts set in a rectangle.
A. each a roof of poles and arrowweed
B. each a roof of poles and arrowweed that are being
C. with each being a roof of poles and arrowweed
D. with roofs of poles and arrowweed to be
E. with roofs of poles and arrowweed that are
这道题应该选A


以上的这些例子都是属于独立主格结构的题型，大家目前应该都有点感觉，但具体独立主格结构是什么，该怎么样判断和使用独立主格结构，相信大家一定还不是非常清楚。

这个专题，夏老师就告诉你们怎么样判断独立主格结构，甚至我们在GMAT写作中也能自由使用独立主格结构这种高级技巧，相信这种技巧使用起来就像篮球场上的crossover, 或者足球场上的马赛旋转一样，引来一片尖叫。

先看看我给独立主格结构下的定义：
所谓独立主格结构（absolute construction），是指句法上游离于句子主体之外，跟主句没有任何句法以及语法方面的联系；但其在意义上却与主句紧密联系在一起，共同构成一个完整的语义环境。独立主格结构没有谓语，只有逻辑上的主语，因此，它在句法上不是句子，而是一个独立于句子成分之外的独特结构形式。 独立主格结构可置于句首、句尾，用逗号与主句隔开。

这句话很抽象，我们来看几个具体的例子：

I heard that she got injured in the accident，my heart full of worry．我听说她在这场事故中受了伤，内心充满担忧。
He stood silent in the moon-light，his door open．月光下，门开着，他默默地站立在那。
Winter coming，it gets colder and colder．冬天来了，天气越来越冷了。
More time given，we should have done it much better．如果给我们更多的时间，我们会做得更好。
The boy stood there，his right hand raised．那个男生站在那里，右手高举。
Here are the first two volumes，the third one to come out next month．这是前两卷，第三卷将于下月问世。
The huntsman entered the forest，gun in hand．那位猎人手里提着枪走进了树林。
Nobody in，the thief took a lot of things away．由于没有人，小偷拿走了许多东西。
Lunch over，he left the house．午饭结束，他离开屋。
He fought the wolf，a stick his only weapon．他和狼搏斗着，唯一的武器是一根棍棒。

发现规律了没有？还没发现规律吗？
以上这些句子，都是以逗号隔开的，其中一个部分是主句，主谓宾成分完美无缺，但另外一个部分似乎不是个完整的句子，缺少了啥？ 对，缺少了一个be动词。也就是说，如果我们把be动词加到这个部分中，这个句子就是一个完整的句子，完美无缺。而且和主句在逻辑上是有联系的，所以我们可以用分号连接它们。

比如：
I heard that she got injured in the accident，my heart full of worry．
I heard that she got injured in the accident; my heart was full of worry．

He stood silent in the moon-light，his door open．
He stood silent in the moon-light; his door was open．

Winter coming，it gets colder and colder．
Winter is coming; it gets colder and colder．

More time given，we should have done it much better．
More time is given; we should have done it much better．

The boy stood there，his right hand raised．
The boy stood there; his right hand was raised．

Here are the first two volumes，the third one to come out next month．
Here are the first two volumes; the third one is to come out next month．

The huntsman entered the forest，gun in hand．
The huntsman entered the forest，gun was in hand．

Nobody in，the thief took a lot of things away．
Nobody was in; the thief took a lot of things away．

Lunch over，he left the house．
Lunch was over; he left the house．

He fought the wolf，a stick his only weapon．
He fought the wolf; a stick was his only weapon．

这个规律简单到了极点，发现了没有。给独立主格结构加上be动词以后，这个句子就是个完整的句子，从逻辑上来说，这个句子和主句可以是各种关系，比如可以是并列，转折，因果，伴随等等。使用独立主格结构以后，那些表示它们之间关系的连词也没了。但读者一定能理解。

这样我们自己也可以造句了，自己设计独立主格结构，只要把其中的一个句子的be动词去了就行，比如说
His work is done; he sat down for a cup of tea.
His work done, he sat down for a cup of tea.

Hong Kong was beautiful, because thousands of lights were on at night．
Hong Kong was beautiful, thousands of lights on at night.

是不是非常简单非常方便？
但是，细心的同学会问，如果那句话里面没有be动词怎么办呢？ 问得好，如果这句话没有be动词，我们就给他加上be动词，然后变成独立主格结构的时候再把这个be动词给删了，有人说，你这不啥都没做嘛。错，加了be动词后其他地方是需要有变化的。
比如：The rain has stopped ；he went out for a walk.
把这前半部分加入be动词怎么办，就是The rain is having stopped (不像个句子，但没办法，be动词后面的动词一定都是要加ing的) ， 然后再把be动词删了这个句子就是: The rain having stopped, he went out for a walk.

到此为止，80%的独立主格结构情况，你都能掌握了，但是还有20%是什么呢？
另外20%的比较特殊的独立主格我们需要注意的是：

There be 句子变成独立主格结构不能只是把be去了，而是需要把be变成being：比如there being no taxi, we had to walk home.

With 后面可以引导独立主格结构： 注意with是介词，不是连词，表示一种伴随状况。比如，With a boy leading the way，they started towards the village．Boy和leading之间省略was，构成独立主格。
With you to help us，we will finish the task in time．You和to之间省略了are，构成独立主格结构。

类似同位语的一种独立主格结构表示想强调前面整句话，或者想强调前面某句话的某一个部分，比如我们一开始的几道GMAT真题中的第2道题和第3道题。第二道强调了前面提到的interactions, 第三道题强调了前面的整句话作为一个event怎么样。这种独立主格结构我成为“披着同位语衣服的独立主格”。

到此为止，我们了解了独立主格结构的基本面貌，相信以后大家就可以使用独立主格结构了。是不是很酷啊？告诉你们一个经验性的规律，a rule of thumb，GMAT考试中的SC考题，如果中间出现了独立主格结构，有超过80%的可能性该独立主格结构就是一个正确选项。