如何写好托福独立写作开头段
托福独立写作是需要30分钟时间完成的300字以上的作文，也就是给出一个话题或者一个论述，然后考生需要用一篇文章来表达自己针对这个话题的观点。很多同学看到这样的任务都会觉得非常难，但是独立写作都是有“套路”的，现在就让我们一起来看看独立写作应该如何写好开头段。
如何写好托福独立写作开头段
开头段又叫introduction段，它的作用是引入话题，并且综合概述全文观点，所以它的组成有两部分：
? General statements (to give background information)
? Thesis (to show the main theme in the essay)
意思就是一开始需要用一两句话来给出背景信息，来说明这篇文章主要谈论的是什么，然后再用一句话写明这篇文章的主题，也就是亮明自己的观点。
我们来看一个例题：
? Do you agree or disagree with the following statement? The invention of the Internet has had negative effects on your civilization. Use specific reasons and examples to support your opinion.
题目翻译：你同意或者不同意以下观点?网络的发明对于文明有消极影响。用具体的原因和例子来支持你的观点。
首先确定观点，这里假如我们采取支持的观点。
然后写出全文的主题句，也就是第一段的最后一句，写这句话的要点是把你的观点具体化：
The Internet enables us to communicate more easily, save time, and save money.
(网络能够使我们交流更容易，节约时间，节约金钱)
然后写前面的主题引入部分，也就是在你要谈论的主题上进行适当拓展，介绍它的大环境，和人们对于它的一些普遍观点：
People have always been worried about the impact when new technology is introduced. For instance, business people are worried about profits since a new technology can make their company obsolete. Yet, progress itself is not negative. The positive or negative impact of technology results from how it is used. One recent development in technology, the Internet, has both positive and negative potential. However, overall, I feel that the Internet is positive for society since it enables us to communicate more easily, save time, and save money.
这就是一个完成度很高的介绍段。
接下来我们看一些介绍段的高分句型：
Some people say that it is most important to protect the environment against pollution.一些人说……
Others say that it is more important to create jobs, even if pollution is a result.另一些人说……
I agree/disagree with the view that …我同意/不同意_观点……
There are several/ a number of reasons that 我同意/不同意的原因是……
There is no doubt in my mind that/There is no question that… 对于……的观点我确信无疑
好了，让我们来做一些练习，请写出下列题目的开头段：
? Do you agree or disagree with the following statement? Classmates are a more important influence than parents are on a child’s success in school. Use specific reasons and examples to support your answer.
? Some people say that computers have made life easier and more convenient. Other people say that computers have made life more complex and stressful. What is your opinion? Use specific reasons and examples to support your answer.
? It is better for children to grow up in the countryside than in a big city. Do you agree or disagree? Use specific reasons and examples to develop your essay.
托福范文：Obtaining Fresh Water from Icebergs
范文的题目是：Obtaining Fresh water from icebergs。
The concept of obtaining fresh water from icebergs that are towed to populated areas and arid regions of the world was once treated as a joke more appropriate to cartoons than real life. But now it is being considered quite seriously by many nations, especially since scientists have warned that the human race will outgrow its fresh water supply faster than it runs out of food.
Glaciers are a possible source of fresh water that has been overlooked until recently. Three-quarters of the Earth’s fresh water supply is still tied up in glacial ice, a reservoir of untapped fresh water so immense that it could sustain all the rivers of the world for 1,000 years. Floating on the oceans every year are 7,659 trillion metric tons of ice encased in 10000 icebergs that break away from the polar ice caps, more than ninety percent of them from Antarctica.
Huge glaciers that stretch over the shallow continental shelf give birth to icebergs throughout the year. Icebergs are not like sea ice, which is formed when the sea itself freezes, rather, they are formed entirely on land, breaking off when glaciers spread over the sea. As they drift away from the polar region, icebergs sometimes move mysteriously in a direction opposite to the wind, pulled by subsurface currents. Because they melt more slowly than smaller pieces of ice, icebergs have been known to drift as far north as 35 degrees south of the equator in the Atlantic Ocean. To corral them and steer them to parts of the world where they are needed would not be too difficult.
The difficulty arises in other technical matters, such as the prevention of rapid melting in warmer climates and the funneling of fresh water to shore in great volume. But even if the icebergs lost half of their volume in towing, the water they could provide would be far cheaper than that produced by desalinization, or removing salt from water.
托福范文：Vision
Human vision like that of other primates has evolved in an arboreal environment. In the dense complex world of a tropical forest, it is more important to see well that to develop an acute sense of smell. In the course of evolution members of the primate line have acquired large eyes while the snout has shrunk to give the eye an unimpeded view. Of mammals only humans and some primates enjoy color vision. The red flag is black to the bull. Horses live in a monochrome world t visible to human eyes however occupies only a very narrow band in the whole electromagnetic spectrum. Ultraviolet rays are invisible to humans though ants and honeybees are sensitive to them. Humans though ants and honeybees are sensitive to them. Humans have no direct perception of infrared rays unlike the rattlesnake which has receptors tuned into wavelengths longer than 0.7 micron. The world would look eerily different if human eyes were sensitive to infrared radiation. Then instead of the darkness of night, we would be able to move easily in a strange shadowless world where objects glowed with varying degrees of intensity. But human eyes excel in other ways. They are in fact remarkably discerning in color gradation. The color sensitivity of normal human vision is rarely surpassed even by sophisticated technical devices.
托福范文：Coal-fired Power Plants
范文的题目是：Coal-fired power plants。
The invention of the incandescent light bulb by Thomas A. Edison in 1879 created a demand for a cheap, readily available fuel with which to generate large amounts of electric power. Coal seemed to fit the bill, and it fueled the earliest power stations. (which were set up at the end of the nineteenth century by Edison himself). As more power plants were constructed throughout the country, the reliance on coal increased throughout the country, the reliance on coal increased. Since the First
World War, coal-fired power plants had a combined in the United States each year. In 1986 such plants had a combined generating capacity of 289,000 megawatts and consumed 83 percent of the nearly 900 million tons of coal mined in the country that year. Given the uncertainty in the future growth of the nearly 900 million tons of coal mined in the country that year. Given the uncertainty in the future growth of nuclear
power and in the supply of oil and natural gas, coal-fired power plants could well provide up to 70 percent of the electric power in the United States by the end of the century.
Yet, in spite of the fact that coal has long been a source of electricity and may remain on for many years(coal represents about 80 percent of United States fossil-fuel reserves), it has actually never been the most desirable fossil fuel for power plants. Coal contains less energy per unit of weight than weight than natural gas or oil; it is difficult to transport, and it is associated with a host of environmental issues, among them acid rain. Since the late 1960’s problems of emission control and waste disposal have sharply reduced the appeal of coal-fired power plants. The cost of ameliorating these environment problems along with the rising cost of building a facility as large and complex as a coal-fired power plant, have also made such plants less attractive from a purely economic perspective.
Changes in the technological base of coal-fired power plants could restore their attractiveness, however. Whereas some of these changes are intended mainly to increase the productivity of existing plants, completely new technologies for burning coal cleanly are also being developed.
