计算机病毒（Computer Virus ）可以定义为： “编辑或者在微机程序中插入的破坏微机功能或者破坏数据，影响微机使用并且能够自我复制的一组微机指令或者程序代码。（）

A computer virus ______.

A．is the same as a biological virus

B．is also an organism

C．is a series of electronic commands

D．is one of biological viruses

mputers were slowed or shut down. But no information was lost. A computer virus is similar to a biological virus--an organism (生物体) that can harm the human body. A computer virus is a series of electronic commands that can harm a computer or the information in the computer. It infects the device (设备) secretly. It tells the computer to do something the computer's owner does not want it to do. For example, a virus could enter a bank's computer system. It might tell the system to destroy all information about money belonging to everyone with the first name United States several months ago. The virus was created by a university student studying computer science. The computers affected by the virus were in major universities, government agencies (政府机关) and private (私人) companies. They were part of a United commands in a computer at his school. The computer sent the commands to other computers through the linked telephone lines.

The virus told each computer to make many copies of itself. Within a few minutes, all the computers' power was being used to make copies of the virus. The computer could do no other work. It finally slowed down greatly, or simply stopped working. Computer experts spent many days trying to destroy the virus in the computer system.

The experts agree the virus could have been much worse. They say it could have sent orders to destroy huge amounts of electronic information.

Many experts believe, the recent computer virus showed the need for better computer security (安全). But that is a problem. The affected system provides a free exchange (交换) of ideas and information among universities, private companies and government offices. Increasing security too much would destroy this exchange. It would slow progress on many important research projects.

Which of the following statements is true？

A．Many computers were attacked by a virus in the U. S.

B．Many computers attacked by a virus in the U.S. lost their information.

C．A computer virus can harm human body.

D．A computer virus can help the computer owner do many things.

The virus can affect the computers in the computer system by ______.

A．turning off the power

B．making them copy itself

C．sending them copies of itself

D．sending them some destructive ordens directly

A.法律地位

B.病毒

C.疟疾

A.They did not realize how terrible the virus was until they were broken by it

B.They did not conscious of how terrible the virus was until they were broken by it

C.They were not conscious of how terrible the virus was until they were broken by it

D.They were not aware of how terrible the virus was until they were broken by it

A.to

B.in

C.via

D.around

H-live-n-one virus in the passage means ______.

A. farm birds

B. infected farm animals

C. people died in Hong Kong

D. a different kind of bird flu virus

A.affected

B.infected

C.effected

D.defected

A.朊病毒(prion)

B.病毒(Virus)

C.立克次体

D.支原体

fluenzalike cases. Influenza is sometimes called "flu" or a "bad cold". He took samples from the throats of patients and in his hospital was able to find the virus of this influenza.

There are three main types of influenza virus. The most important of these are types A and B, each of them having several sub-groups. With the instruments at the hospital the doctor recognized that the outbreak was due to a virus group A, but he didn't know the sub-group. He reported the outbreak to the World Health Organization in Geneva. WHO published the important news alongside reports of a similar outbreak in Hong Kong, where about 15%～20% of the population had become ill.

As soon as the London doctors received the package of throat samples, they began the standard tests. They found that by reproducing itself at very high speed, the virus had multiplied more than a million times within two days. Continuing their careful tests, the doctors checked the effect of drugs used against all the known sub-groups of type A virus. None of them gave any protection. This then, was something new; a new influenza virus against which the people of the world had no ready help whatsoever.

Having isolated the virus they were working with, the doctors now conducted tests on some specially selected animals, which contracted influenza in the same way as human beings did. In a short time the usual sign of the disease disappeared. Theses experiments revealed that the new virus spread easily, but that it was not a killer. Scientists, like the general public, called it simply "Asian" flu.

The influenza discovered by a doctor in Singapore is caused by ______.

A．a new type of virus

B．type A virus

C．a sub-group of type B virus

D．a virus only existing in Asia