求助prep语法

昨天第一次做了prep，成绩不理想，最让人难受的是语法比平时练习的更加摸不到头脑。烦请各位过路的nn给予帮助，小妹万分感激！！！！

In the Louisiana Purchase of 1803, the United States acquired 828,000 square miles for about four cents an acre, which more than doubled the country's size and that brought its western border within reach of the PAcific Ocean.

A

B For about four cents an acre the United States acquire, in the Louisiana Purchase of 1803, 828,000 square miles, more than doubling the country's size and it brought 

C With the Louisiana Purchase of 1803,the United States acquired 828,000 square miles for about four cents an acre, more than doubling its size and bringing

D The United States, in the Louisiana Purchase of 1803, for about four cents an acre, acquired 828,000 square miles, more than doubling the country's size, bringing

E Acquiring 828,000 square miles in the Louisiana Purchase of 1803, the United States bought it for about four cents an acre, more than doubling the country's size and bringing

答案是C，但是我觉得D比C好啊。C的With结构在这里好像不是很合适啊……哎，nn们，能解释下给我吗？

In AD 391,resulting from the destruction of the largest library of the ancient world at Alexandriea, later generations lost all but the IIiad and Odyssey among Greek epics, most of the poetry of Pindar and Sappho, and dozens of plays by Aeschylus and Euripides.

A

B.the destroying of the largest library of the ancient world at Alexandriea resulted and

C.because of the result of the destruction of the library at Alexandriea,the largest of ancient world

D.as a result of the destruction of the library at Alexandriea, the largest of the ancient world,

E.Alexandriea's largest library of the ancient world was destroyed, and the result was

答案是D,但是A为什么不好呢？    

In Scotland, the number of world salmon have been reduced because of uncontrolled deep-sea and coastal netting, by pollution, and by various other threats to the fish's habitat.

A

B number of wild salmon is reduced because deep-sea and coastal netting is not controlled,

C numbers of wild salmon has been reduced because of uncontrolled deep-sea and coastal netting,

D wild salmon's numbers are reduced by deep-sea and coastal netting that is not controlled,

E wild salmon's numbers have been reduced by uncontrolled deep-sea and coastal netting,

答案是E,我可以看出来 reduced by.....,by....and by....的结构。但是不明白为什么是numbers呢？我觉得应该是the number啊？？

不好意思，版主，知道了！多谢！！！

版主虽然很忙，但我好闲丫蛋teng

mm，我虽然不是nn，但好想向您推荐呢（loli腔？）

扯够了，开始做题，点评在每个选项后面

先贴一段wikipedia的讲解

汉语版的先，注意高亮显示

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英语（English）属于印欧语系中日耳曼语族下的西日耳曼语支，由古代从欧洲大陆移民大不列颠岛的盎格鲁、撒克遜和朱特部落的日耳曼人所说的语言演变而来，并通过英国的殖民活动传播到世界各地。由於在歷史上曾和多種民族語言接觸，它的詞彙從一元變為多元，語法從“多屈折”變為“少屈折”，語音也發生了規律性的變化。根据以英语作为母语的人数计算，英语可能是世界上第三大或第四大语言（1999年统计为380,000,000人），但它是世界上最广泛的第二语言。世界上60%以上的信件是用英语书写的，50%以上的报纸杂志是英语的。上两个世纪英国和美国在文化、经济、军事、政治和科学上的领先地位使得英语成为一种准国际语言。英语是联合国的工作语言之一。

http://zh.wikipedia.org/wiki/%E8%8B%B1%E8%AF%AD

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什么叫少屈折？

就是有p就快放（什么？抗议我太通俗了？小沈阳能放我不能放？妈妈的！）

再贴英文的，同样，注意高亮

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Grammar

English grammar has minimal inflection compared with most other Indo-European languages. For example, Modern English, unlike Modern German or Dutch and the Romance languages, lacks grammatical gender and adjectival agreement. Case marking has almost disappeared from the language and mainly survives in pronouns. The patterning of strong (e.g. speak/spoke/spoken) versus weak verbs inherited from its Germanic origins has declined in importance in modern English, and the remnants of inflection (such as plural marking) have become more regular.

At the same time, the language has become more analytic, and has developed features such as modal verbs and word order as resources for conveying meaning. Auxiliary verbs mark constructions such as questions, negative polarity, the passive voice and progressive aspect.

http://en.wikipedia.org/wiki/English_language

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enough smalltalk

let's get to the real deal

每个选项的点评在their后面

根据主谓一致，AC残废，送佛归殿吧

根据倒数第二个逗号，可以判定前面确实少了一个by

不满足这个需求的只有B，阿弥陀佛，贫僧不送

DE开比

哈哈，D的by明显没有在和后面并列，因为by后面要求是一个词，而D是一个从句，a clause

因为还要去取真经，去西天的任务，只能交给D了

做完

您的问题是不明白俩词的区别

记住一个原则，当您比不出意思差别的时候

不要硬来

另外，GMAT是一项客观性很强的考试

当您用“我觉得”开始一个自省的句子的时候

要小心了

regards