2008公共英语二级(PETS2)考试模拟试卷八(6)

文章作者 100test 发表时间 2007:12:15 12:29:18
来源 100Test.Com百考试题网

Section Ⅲ Reading Comprehension

　　说明：阅读下列短文，从[A]、[B]、[C]、[D]四个选项中选择一个正确答案。

　　A computer virus (病毒) is a software (软件，计算方法) program that attaches itself to another program in computer memory or on a disk, and spreads from one program to another. Viruses can damage data, cause computers to crash (瘫痪), display (显示，陈列) bother some messages, or lie sleeping until such time they are set to "awake". In todays industry, scanning (扫描) is a necessity (需要，必然，必需品). Computer viruses no longer attack your computing environment (环境，周围状况) only, but all other computing environments which you contact. Computer viruses can attach themselves to the files being used and later spread themselves through disks and files. Important information and hardware (五金制品，硬件) losses could come to your computing environment, if you are not careful enough.

　　Many anti-virus products, such as KV 300 and VirusScan, help to act against viruses. Scheduled regular scans of your computing environment can help you to practice "safe computing".

56.A computer virus is 　　.

　　lonely　　　　　　not contagious　　contagious　　　　programmed　　
　　

57.Computer viruses can cause 　　.

　　bothers and messages　

　　people to have colds　

　　great harm to data or the computer system (系统，制度)　

　　sleeping lies and the computer system　

58.We have to be on the alert (机警的，活泼的，使…警觉) against 　　.

　　scanning　　　　　information 　　　environment 　　　viruses 　　
　　　

59.Whats meant (意指，意味着) by "safe computing"?

　　Know todays industry much better.　

　　Have your computer a better environment.　

　　Have more practices in computer.　

　　Have regular scans of your computer.　

　　A heat pump is a single electric system (系统，制度) that both heats and cools. In summer, a heat pump is a conventional (普通的，习惯的) air conditioner which removes heat from a building. In winter, the system reverses itself to use the natural heat that is always present in outdoor air. By taking advantage of the free heat, a heat pump is more economical (节约的) to operate in winter than a system using electric resistance (阻力，抵抗，电阻) heat. Electric resistance heat uses electricity as a raw (生的，天然的) material to create (创造，产生) heat where no heat existed before. Heat pump, on the other hand, uses electricity to move existing heat from where it already exists naturally (outdoors) to where it is wanted (indoors (在室内)).

　　Heat energy will naturally flow from areas of greater concentration to areas of lesser (较少的，次要的) concentration. That is what happens when hot food grows cool. The heat from the food flows into the air in the room until the food stabilizes at room temperature. Blowing air over substance (物质，本质，主要部分) will speed up the process (过程，工序，诉讼，加工), which is why a winter day will seem cold when there is a strong wind than when the air is still.

　　A heat pump uses this heat transfer (转移，转让，改乘) process to move heat which is always in the air. The outdoor coil (线圈，卷) is made colder than the outdoors air. A fan blows outdoor air across the coil where heat is absorbed by the refrigerant (冷却剂). The refrigerant is then compressed and moved to the indoor coil and the heat is distributed in the building.

　　During the summer, a heat pump reverses this process. The indoor coil is made cooler than the indoor air, and so room heat flows into the refrigerant which is compressed and moved to the outdoor coil. The outdoor coil, which is hotter than the outdoor air, will lose heat energy.

60.A heat pump is used 　　.

　　to cook 　　　　　to heat 　　　　　to cool 　　　　　to heat and cool　

61.A heat pump is used to make the room comfortable by using 　　.

　　electric resistance heat　

　　natural heat and cool　

　　coal energy　

　　petrol (汽油) energy　

62.Which of the following facts is true?

　　A heat pump is used both in summer and in winter.　

　　A heat pump is only used in summer.　

　　A heat pump is only used in winter.　

　　A heat pump is only used at night.　

63.How can we make the substance cool quickly?

　　Blow cold air over it.　

　　Put is in the room.　

　　Cover it with something.　

　　Blow hot air over it.