You have just come back from the U.S. as a member of a Sino-American cultural exchange program. Write a letter to your American colleague to

1)express your thanks for his/her warm reception;

2)welcome him/her to visit China in due course.

You should write about 100 words.

Do not sign your own name at the end of the letter. Use "Zhang Wei" instead.

Do not write your address.

Part B (10 points)

[A] Anti-virus software often bounces a warning back to the sender of an infected e-mail, saying that the e-mail in question cannot be delivered because it contains a virus. SoBig. F was able to spoof this system by" harvesting" e-mail addresses from the hard disks of infected computers. Some of these addresses were then sent infected e-mails that had been doctored to look as though they had come from other harvested addresses. The latter were thus sent warnings, even though their machines may not have been infected.

[B] Blaster worked by creating a "buffer overrun in the remote procedure call". In English, that earns it attacked a piece of software used by Microsoft's Windows operating system to allow one computer to control another. It did so by causing that software to use too much memory.

[C] Though both of these programs fell short of the apparent objectives of their authors, they still caused damage. For instance, they forced the shutdown of a number of computer networks, including the one used by the New York Times newsroom, and the one organizing trains operated by CSX, a freight company on America's east coast. Computer scientists expect that it is only a matter of time before a truly devastating virus is unleashed.

[D] Most worms work by exploiting weaknesses in an operating system, but whoever wrote Blaster had a particularly refined sense of humour, since the website under attack was the one from which users could obtain a program to fix the very weakness in Windows that the worm itself was exploiting.

[E] One way to deal with a wicked worm like Blaster is to design a fairy godmother worm that goes around repairing vulnerable machines automatically. In the case of Blaster someone seems to have tried exactly that with a program called Welchi. However, according to Mr. Haley, Welchi has caused almost as many problems as Blaster itself, by overwhelming networks with "pings" signals that checked for the presence of other computers.

[F] SoBig. F was the more visible of the two recent waves of infection because it propagated itself by e-mail, meaning that victims noticed what was going on. SoBig. F was so effective that it caused substantial disruption even to those protected by anti-virus software. That was because so many copies of the virus spread (some 500,000 computers were infected) that many machines were overwhelmed by messages from their own anti-virus software. On top of that, one common counter-measure backfired, increasing traffic still further.

[G] Kevin Haley of Symantec, a firm that makes anti-virus software, thinks that one reason SoBig. F was so much more effective than other viruses that work this way is because it was better at searching hard-drives for addresses. Brian King, of CERT, an internet-security centre at Carnegie-Mellon University in Pittsburgh, notes that, unlike its precursors, SoBig. F was capable of "multi-threading": it could send multiple e-mails simultaneously, allowing it to dispatch thousands in minutes.

(41)

某计算机的I／O设备：采用异步串行传送方式传送字符信息。字符信息的格式为1位起始位、7位数据位、1位校验位和1位停止位。若要求每秒传送560个字符，则该串行设备的数据传送率为_______波特。

Part B (10 points)

In the following text, some sentences have been removed. For Questions 41-45, choose the most suitable one from the list (A、B、C、D、E、F、G……) to fit into each of the numbered blank. There are several extra choices, which do not fit in any of the gaps. (10 points)

The race to select the Beijing 2008 Olympic mascot is heating up and from all accounts the panda is out in front. According to news reports, the Sichuan panda team is pulling out all the stops to get the giant panda chosen—not surprisingly, as most of the pandas in China can be found in Sichuan. (41)______.

So what does an Olympic mascot represent to the world？ The Sichuan team says that the giant panda represents the peace and harmony of the Olympic spirit, but is that what a panda really portrays？ What, after all, does a giant panda do all day？ It pulls down bamboo shoots and eats, and when it's not eating, it sleeps. That's it! That is all a panda does. (42)______.

Fortunately there are other candidates for the honor of representing the Beijing Olympics, including the Chinese tiger. Now there's a contrast with the panda! The tiger is sleek; the tiger is swift. When the tiger springs into action, one can see its muscles ripple with energy; When a tiger is hunting for food, first it stalks its prey, perhaps a herd of wild swine. Then it chooses a victim and cleverly plans its strategy for the chase. Carefully choosing its moment, the tiger takes off with power and speed, as much as 80 km per hour. (43)______. The tiger is sleek, strong, swift and uses clever strategy to achieve its goal. Is it not the ideal animal to represent the athletes who have planned and carried out Icing-term strategies to qualify for the Olympics？

(44)______. However, the tiger, like most predatory animals, is not truly vicious—this is a common misperception. Under normal circumstances it kills only for food. When hungry it goes after its prey with fierce determination. it not take fierce determination for an athlete to win a medal in the Olympics？

Some years ago, Shell carried out a very successful ad campaign in Canada and the US. The ads showed a tiger getting into the gas tank of an auto; the accompanying slogan was "Put a tiger in your tank!" (45)______. Nowadays China is amazing everyone with the power and speed of its economic development, far outstripping the other nations of the world. In the latest Olympics, the Chinese athletes surprised the world not only with the number of medals they won but also with the categories in which they won them. I would therefore argue that Beijing's 2008 Olympic mascot should be an animal that embodies the great qualities, power and speed, of the Chinese athletes and their homeland—the Chinese tiger.

A. One might say that the giant panda is fat and lazy! What if there is no bamboo？ Does it find other food？ No. When the panda's food disappears, the panda disappears. In fact, the giant panda is a very vulnerable animal and that is why today it is at risk of extinction. Do Chinese really want a fat, lazy animal for their Olympic mascot？

B. Everyone understood the message: the tiger meant extra power and speed for your car. The original Olympics in Greece brought together athletes in a fierce trial of power and speed.

C. Recently it was brought to my attention that the 1988 Seoul Olympics had a tiger mascot. Does this make the tiger ineligible for use in the 2008 Beijing Olympics？ In an informal poll of my friends and colleagues, I discovered that no one remembered the mascot of the 1988 games. In fact, they did not remember the mascot of the Sydney Olympics or even of this year's Athens Olympics.

D. They have created 29 possible panda designs for consideration by the Beijing Olympic organizing committee, which will be making the choice.

E. To be sure, the giant panda seems loveable whereas the tiger might be thought by some t

举例说明动机强度与工作效率的关系。

画图说明政府税收对产品均衡价格的影响。