托福阅读之段落结构题目的解决方法

 在托福阅读中，大家慢慢就会发现很多文章整体都是结构非常明晰的，总体都是总-分或者总-分-总的形式。总-分的形式就是段落开始为段落主题句，其他部分为支撑的细节，具体论证方式有对比比较、定义、举例、分类、提供数据支持、类比、过程描述等，此时的段落目的对应段落开始的主题句。有时题目还会问一个段落在整篇文章中的作用。都是对结构的把控与调查。

例如，

例一(总-分结构)

Paragraph 7: About 90 percent of modern humans are right-handed: we are the only mammal with a preferential use of one hand. The part of the brain responsible for fine control and movement is located in the left cerebral hemisphere, and the findings above suggest that the human brain was already asymmetrical in its structure and function not long after 2 million years ago. Among Neanderthalers of 70,000–35,000 years ago, Marcellin Boule noted that the La Chapelle-aux-Saints individual had a left hemisphere slightly bigger than the right, and the same was found for brains of specimens from Neanderthal, Gibraltar, and La Quina.

What is the author's primary purpose in paragraph 7?

(A) To illustrate the importance of studying the brain

(B) To demonstrate that human beings are the only mammal to desire fine control of movement

(C) To contrast the functions of the two hemispheres of the brain

(D) To demonstrate that right-hand preference has existed for a long time

参考译文：

大约90%的现代人类是右撇子:我们是唯一优先使用一只手的哺乳动物。大脑中负责精细控制和运动的部分位于左大脑半球，上述发现表明，人类大脑在200万年前不久，其结构和功能就已经不对称了。在7万到3万5千年前的尼安德特人当中，Marcellin Boule注意到La Chapelle-aux-Saints个体的左半球略大于右半球，尼安德特人、直布罗陀人和拉奎那人的大脑样本也发现了同样的现象。

A选项 说明研究大脑的重要性

B 证明人类是唯一一种渴望精细控制运动的哺乳动物

C 对比大脑两个半球的功能

D 来证明右手偏好已经存在很长时间了

根据文章的整体表达，可以判断第一句为主题句，后面都在解释说明。所以第四个选项为正确答案。文章其实主要描述大脑左半球的功能，未与大脑右半球的功能进行比较，所以第三个选项为错误选项。

再看下面这篇文章，它的机构就比较清晰。开始说会造成严重的环境问题。后面特别是Finally, 都在证明问题是什么。

Paragraph 6: Moreover, getting petroleum out of the ground and from under the sea and to the consumer can create environmental problems anywhere along the line. Pipelines carrying oil can be broken by faults or landslides, causing serious oil spills. Spillage from huge oil-carrying cargo ships, called tankers, involved in collisions or accidental groundings (such as the one off Alaska in 1989) can create oil slicks at sea. Offshore platforms may also lose oil, creating oil slicks that drift ashore and foul the beaches, harming the environment. Sometimes, the ground at an oil field may subside as oil is removed. The Wilmington field near Long Beach, California, has subsided nine meters in 50 years; protective barriers have had to be built to prevent seawater from flooding the area. Finally, the refining and burning of petroleum and its products can cause air pollution. Advancing technology and strict laws, however, are helping control some of these adverse environmental

参考译文：

此外，从地下开采石油、从海底开采石油并输送给消费者，可能会在沿线的任何地方造成环境问题。输送石油的管道可能因断层或山体滑坡而断裂，导致严重的石油泄漏。大型油轮(油轮)发生碰撞或意外搁浅(比如1989年在阿拉斯加附近发生的那次)，可能会造成海上浮油。海上平台也可能失去石油，造成浮油漂到岸上，污染海滩，损害环境。有时候，油田的地面会随着石油的开采而下沉。加利福尼亚长滩附近的威尔明顿油田50年来已经下沉了9米;为了防止海水淹没该地区，必须建立防护屏障。最后，石油及其产品的精炼和燃烧会造成空气污染。然而，先进的技术和严格的法律正在帮助控制这些不利的环境