说明文 (Exposition)写作
说明文是用说明的表达方式来解说事物、阐明事理的文章，以解释、阐述事物的形状、特征、性质、成因、关系、功能、作用为目的。而说明是对事物的发生、发展、结果、特征、性质、状态、功能等进行解释、介绍、阐述的一种基本表达方式。
可用于事物说明的写作手法很多， 鉴于六级写作的趋势，这里着重介绍四种类型的说明文。
1. 举例说明文
通过举例或列举阐明事理的写作方法。为使读者弄清某一事理，或使抽象化概念形象化或具体化，作者拿出文章的较大篇幅 进行举例说明，以进一步证明所述道理的真实性和可行性。
2. 知识性说明文
通过解释说明来阐明事实、道理或介绍知识、信息等的写作手法。从整篇文章看，此类作文旨在为读者提供并未知晓的知识和信息。读者通过阅读此类文章通达事理，懂得该怎么办。
3. 对比说明文
通过对两种事物进行对比或比较，找出两者之间的共同点或对立点的写作手法。为说明某一事物在不同条件下的差异，或此事物与同类或不同类事物的差别，作者往往采用比较和对比的手法来获得分清事理的写作效果。读者从比较或对比说明中获得教益。
4. 定义说明文
通过揭示概念的内涵或下定义的方式来明确概念的写作方法。旨在给事物的性质和特点下定义，回答“什么是……”和“怎样理解……”之类的问题。故此，这类作文要求作者具备科学严谨的文风，定义要下得准确合理，文字说明要全面到位。作者常常会借助举例说明的手法或比较说明的手法达到界定事物的目的。
在实际写作中，作者一般在同一篇文章中运用多种手法达到说明事物的写作目的，运用单一手段者甚少。
Sample 1
The Potential of Internet Education
Internet is getting into people’s life and becoming more and more popular. Experts are now working on setting up a national long-distance educational system in China to provide educational opportunities via Internet.
In reality, the educational via Internet plan has been taking shape. Some universities have already got involved in regional long-distance education, catching the attention of many educators and computer experts worldwide. Others have just connected their campus computers for teaching and research, and provided more opportunities for learner.
The Internet education will be developing dramatically. It’s estimated that computerized long-distance teaching networks will be available by 2010 for postgraduate education, vocational programs, teachers’ training and employees’ training. Moreover, it will soon cover all the corners of the globe and eventually win the worldwide popularity.
评析：
这是篇知识性说明文。文章作者按三段式行文。首段概括说明远程教育越来越普及而且专家们正致力于建立全国互联网教育系统。正文说明我国互联网教育的现状：一些学校正普及区域性的网络教育，引起全国关注；而另一些学校将教育和科研联网，共同开发，机会多多，潜力巨大。文章最后展望了互联网教育的前景，到2010年我国将基本建成远程教育系统。从互联网教育的发展趋势我们可以断定，不久互联网教育将在世界各个角落普及。文章脉络清晰，结构严谨，行文流畅，语义连贯，顺理成章。
Sample 2
Directions: For this part, you are allowed thirty minutes to write a composition on the topic Good Manners in Different Cultures? You should write at least 150 words, and base your composition on the outline (given in Chinese) below:
i. 在许多社交场合一个人举止的好坏显得十分重要。
ii. 举例对比说明不同文化背景下的良好举止。
Good Manners in Different Cultures
In most cases of social contact, nothing reveals more clearly what kind of person one is than his manners. A person with good manners is more welcome anywhere than one of pleasing appearance but with unrefined manners. Yet in different cultures, there are different manners which it is considered worthwhile to cultivate in social life.
When you meet a friend on your way, for instance, it is common sense to say something like “Where are you going?” or “Where have you been?” in the Chinese culture. In Western societies, by contrast, even though both are close friends, it is good manners to avoid greeting like that, for the first reaction of most English-speaking people to such greetings would probably be “It’s none of your business!” The same is true of when a person sneezes. On that occasion, it is taken for granted that some Chinese nearby remarks, “ Someone misses you.” Or humorously” Who is cursing you?”, whereas an American or Englishman would rather like to say, “God bless you!” A guest in an Asian house, if offered something to drink, usually leaves a little to indicate that he has had enough, but in England, a gust always finishes up a drink to show that he has enjoyed it.
As for body languages, not all of them in one culture convey the same message in another culture. In China, it is normally seen as signs of affection to touch, hug or even kiss a friend’s baby. In the eyes of western mothers, on the other hand, such actions can arouse dislike and even hostility from them. The cases cited here can serve only as a reminder that one culture’s meat may sometimes be another culture’s position.
Sample 3
Directions: For this part, you are allowed thirty minutes to write a composition on the topic Computer Viruses. You should write at least 150 words, and base your composition on the outline (given in Chinese) below:
1. 目前电脑系统时常受到病毒感染。
2. 电脑病毒有许多，试举例说出几种。
3. 我们应千方百计杀毒。
Computer Viruses
Computer virus, whose essence component is a set of instructions, is one kind of threat to the security and integrity of computer sys tem. Nowadays computer systems worldwide are often infected by computer viruses. Some cause the loss of programs and date, erase files or subtly alter data. Others even crash computers or make them useless. In this way, each year they cause tens of billions (US$) of losses.
It’s estimated there are about 4500 kinds of computer viruses, being unleashed at the rate of about 5 per day. How terrible! A case in point is “Love Bug” which proclaims “I Love You” in the E-mail subject line. Once the Internet surfer opens the file with “I Love You”, the viruses would copy themselves and destroy valuable computer pictures and video files. Another case in point is the CIH, which is also very destructive. Besides, there are also “Tedious”, “Concept F” and “Explore Zip”, “Romeo & Juliet”, to name only a few.
However, it’s high time for us to work out effective ways to purge the viruses. On the one hand, I hope anti-bug experts would write out more bug killers such as KV 3000 so as to eliminate the bugs. On the other hand, we should enhance the cyber law and force the virus writher to stop playing pranks on the computer users so as to let the world be bug-free.
Sample 4
Directions: For this part, you are allowed thirty minutes to write a composition on the topic Cyber Crimes. You should write at least 150 words, and base your composition on the outline (given in Chinese) below:
1． 网上犯罪的形式很多，如……
2． 网上犯罪的根源。
3． 如何打击网上犯罪现象。
Cyber Crimes
Nowadays cyber criminals seem to be everywhere, with a few clicks, committing all kinds of cyber crimes. To illustrate, some commit fraud or lift intellectual property. Others subvert deals, snatch passwords or disrupt e-commerce. Still others unleash viruses to crash computers. As a result, these hackers do a great damage to companies and computer user, causing computer losses up to 10 billion dollars per year.
Naturally, there are many causes for the cyber crimes. In addition to the wicked nature of the hackers, the frailties of Internet partially nourish the crimes. Just because there are holes in Internet-the complex soft ware is buggy and often infested, the cyber vandals can find out the weakness in the Website software programs and by manipulating software glitches, gain access to Website, committing all kinds of crimes.
However, we shouldn’t tolerate these cyber criminals any more. And it’s high time for us to take all the effective steps to battle the cyber crooks. First we should reinforce the cyber laws to protect the Web, the powerful engine of economy. Besides, we should use high techniques to improve intrusion detection, encryption and computer security. Finally, we should train more talented people to build up more firewalls so as to make the Net immune to all kinds of viruses and unassailable to all a kinds off cyber criminals.
Sample 5
Directions: For this part, you are allowed thirty minutes to write a composition on the topic Hackers. You should write at least 150 words, and base your composition on the outline (given in Chinese) below:
1. 黑客的目的。
2. 试举例说明黑客攻击的目标。
3. 如何打击黑客。
Hackers
Nowadays, hackers, the terrific cyber criminals often hack into Websites for various purposes. Some malicious hackers execute assaults on computers chiefly for some evil purposes. Other profiteers make attacks on e-commerce sites chiefly for financial purposes. Still some others hit Websites either to test their skills or to tease the useless cyber experts for fun.
Hackers have various targets of their web attacks. Some super hackers can penetrate almost all the sites on the Web. And they are esp. enjoy hacking into the safest Websites and government agencies on the Web. Therefore, their first target is the Pentagon, which is “visited” by unwelcome guests for about 20,000 times a year. Interestingly enough even White House can fall victim to hacker. Other hackers aim at attacking the biggest e-commerce sites. A case in point is that Elong. com and Sina.com have been harnessed by hacker. Another case in point is that even the largest Worldwide Website Yahoo was once forced to shut down. As a result, they cause great financial losses each year.
However, it’s high time for us to take all the effective measures to hunt and battle hacker. First, we should deprive them of their tools, such as scans, sniffers etc., with which they can spot out some weaknesses on the Web and make the attacks. Besides, we should work out cyber law and enhance the law management on the Web and increase the punishment of hackers. Finally, we should further develop encryption and try to build more firewalls in order to lock the hackers out.
Sample 6
Directions: For this part, you are allowed thirty minutes to write a composition on the topic My Millennium Dreams. You should write at least 150 words, and base your composition on the outline (given in Chinese) below:
1. 千禧年之际是憧憬未来的最佳时刻。
2. 试举例说明你有哪些千禧年的梦想。
My Millennium Dreams
The new year’s eve naturally brought me into a dream land. In spite of the controversy whether the year 2000 marks the beginning of a new century, I cherished many millennium dreams at that time.
First, I dream we’ll be living in a more beautiful, convenient, fair and secure living environment, with Internet bringing us more convenience, and globalization unprecedented prosperity in economy. I even dream that high-tech will bring us many wonders and even enable us to drive sky-cars or sky –automobiles to visit other planets in the solar system just as we visit our next door neighbors.
Second, I dream that with the successful completion of the working draft of human genome map, the life-span of all the globers will be doubled, and even tripled. And I dream that the future globers will be able to cure whatever incurable diseases.
Third, I dream, with peace and development as an irresistible trend in the 21st century all the globers will be able to live in a harmonious, peaceful and prosperous world. To sum up, I have many, many nice millennium dreams. The above mentioned are only my most wishful dreams.
Sample 7
Directions: For this part, you are allowed thirty minutes to write a composition on the topic The Significance of the First Working Draft of Human Genome Map. You should write at least 150 words, and base your composition on the outline (given in Chinese) below:
1. 人类第一张基因草图的意义重大。
2. 试举例说明其重大意义。
The Significance of the First Working Draft of Human Genome Map
The completion of the first working draft of Human Genome Map is of great significance in human history. It’s so important that it’s often deemed as the biological equivalent of the landing on the moon. Why?
Because, first, decoding the human genome, the secret of human life, is hailed as one of the greatest scientific milestones in the overall progress of the Human Genome Project. Besides, it’s of vital importance to the development of life science. Based on the findings of the project, our life-span might be doubled, or even tripled. Therefore, that’s why we regard the achievement as the common wealth, even the most valuable asset of the whole mankind.
Second, the sketch is of great importance to the development of medicine and pharmaceuticals. Because the great advances in understanding of human genetics can help human beings know more about themselves and how to treat the major diseases, it will enable medical industry to develop fantastically. Therefore, we have every reason to expect the greatest killers in the world, such as cancer and AIDS, will be cured in the near future.
Finally, the working draft of Human Genome Map will greatly promote the development of biological information and technology, and help lay a sold foundation for the biological industry__ the pillar industry in the 21st century.
Sample 8
Directions: For this part, you are allowed thirty minutes to write a composition on the topic Internet in China. You should write at least 150 words, and base your composition on the outline (given in Chinese) below:
1. 因特网在中国的现状。
2. 因特网的用途。
3. 因特网的未来。
Internet in China
With the arrival of the knowledge economy age, Internet, as a new media, has come into our life. Nowadays, getting on the line and using Internet has become popular in China, especially in some big cities. Why is Internet getting so popular in such a short time?
The popularity of Internet results from its great utility. With Internet, it is convenient and fast for people to get a variety of information and what they need is just to press the key buttons. E-mail is another popular use. It can transmit your letter quickly, safely and accurately. Besides, Internet can have some other uses. Doctors may use it to diagnoses and treat their patients by discussing or exchanging experience with doctors in other parts of the world. Students may obtain new knowledge from a nation-long-distance-education-system via Internet. Finally, businessmen can conduct e-commerce or E-business on the Net.
With so many uses and advantages, there is no doubt more and more people will be wired to Internet – the information expressway. In short, with its high speed and efficiency, Internet will be more popular in China in the near future.
Sample 9
Directions: For this part, you are allowed thirty minutes to write a composition on the topic The Internet E-mail. You should write at least 150 words, and base your composition on the outline (given in Chinese) below:
1. 电子邮件开辟了新的通讯渠道且日益普及。
2. 电子邮件给我们带来便利。
3. 电子邮件的发展前景。
The Internet E-mail
E-mail, as an entirely new way of communication by means of computers, is becoming so popular in both developing and esp. developed countries, that it’s difficult to imagine modern life without it.
E-mail is fast, inexpensive and highly efficient. It has brought much convenience to our daily life. First, you can send and receive by E-mail a variety of information and documents such as letters, papers, video and audio files to anyone in over 170 countries in a short time. Moreover, language barriers are not a problem, because the Internet software is capable of translating your mail into whatever language you want. Besides, you can also store, delete, edit, compile and search your E-mail or send it simultaneously to different places. Finally, by defining your own passwords you can always keep your mail a secret.
With the fast expansion of the band-width and wider application of Internet, E-mail will be more and more useful and soon it will become an indispensable means of communication throughout the globe.
Sample 10
Directions: For this part, you are allowed thirty minutes to write a composition on the topic Embracing the Knowledge Economy Age. You should write at least 150 words, and base your composition on the outline (given in Chinese) below:
1. 如今知识经济初见端倪。
2. 知识在知识经济时代中起主导作用。
3. 举例说明你怎样拥抱知识经济的新时代。
Embracing the Knowledge Economy Age
The arrival of the new century has brought us a new message: knowledge economy age is fast taking shape in the world’s scale. Many new academic fields have been explored or established. Still more skills and technologies are emerging every year, every month, even every day. People are surprised to find that knowledge is really exploding at an alarming speed. All this points to the fact that knowledge economy age is rapidly approaching us.
Knowledge economy is an entirely new economic system, in which knowledge plays a dominant role. The possession, manufacture, distribution and consumption of knowledge are the basis of economic activities. Whoever possesses more and newer knowledge will become wealthy. Hence the pursuit of new knowledge will be every individual’s goal and lifelong task.
How can I better embrace the new age? As a working professional graduate, I have already realized how acute the competition will be. So I have made up my mind to make the best use of my time to learn as much knowledge as possible. Even after graduation I will do my best to update my knowledge and master all the necessary skills needed in my future career. Knowledge is strength and wealth. After all, opportunity always benefits the prepared mind.
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