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  • ID:9121-13204
    Passage 3
    Viruses are short strings of software code that have three properties: First, they conceal themselves in legitimate files or programs; second, they replicate like bacteria to spread from machine to machine; and third, they do things to your computer that make you want to tear your hair out.
    There’s no perfect cure. Like the flu, computer viruses evolve. Last year’s immunization isn’t any good for this year’s disease because every time someone invents a new medication(医药), someone else invents a new disease. Nevertheless, a few simple precautions will help you against all but the cleverest hacker.
    For a PC user, he or she should use good virus-checking software. But a word of caution: Not every program fixes every virus, and when a new bug hits, the remedy takes a while to reach the market. A PC user must keep it in his or her mind to back up the data and anyone who doesn’t have a backup drive is begging for trouble. When a new file or application is loaded onto the computer, one should immediately pass it through antivirus software so that the viruses can be caught and killed before they do any harm. If you receive a mail with a file attached to it from someone you don’t know, then do not open that file because these days most viruses and their cousins, networking-infecting worms, are spread through files attached to email or downloaded from the Web. Finally, if your computers are infected, you should not be panic and you should use a friend’s computer to search the Web for a cure.
    Where Viruses are concerned, what grandma used to tell you is extremely relevant: An ounce of prevention is worth a pound of cure.

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  • ID:9121-13125
    __________ those nice days, Elizabeth couldnt help giving out a sigh.

    A. Reflecting of B. Inflecting upon

    C. Reflecting upon D. Inflecting of




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  • ID:9121-11836
    A transformation is occurring that should greatly __1__ living standards in the developing world. Places that __2__ recently were deaf and dumb are rapidly acquiring __3__ telecommunications. Many developing countries are planning to invest vast sums of money __4__ their telecommunications networks to allow them to __5__ with developed countries. They believe this will __6__ foreign and domestic investment. However, how fast these nations should push __7__ is a matter of debate. And some developing countries __8__ experience in weighing costs and choosing between technologies. Vietnam, __9__ particular, though desperate for any phones, requires that all mobile phones be expensive digital models. Still, there is __10__ dispute that communications will be a key factor __11__ the winners from the losers. Over the next decade, China plans to pour some $100 billion into telecommunications equipment. Telecommunications is also a key __12__ Shanghai’s ambition of becoming a top financial center. Shanghai plans to be as electronically advanced __13__ New York. __14__, some other developing countries and areas such as Hungary, Latin America, and Thailand are all hoping to jump into the modern world __15__ means of telecommunication revolution. For countries that have lagged __16__ for so long, the temptation to move ahead in one jump is hard to __17__. And __18__ the mistakes they’ll make, they’ll persist ―__19__ day they can cruise alongside Americans and Western Europeans __20__ the information superhighway.
    8
    A never
    B have
    C lack of
    D lack


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  • ID:9121-12930(本题为引用材料试题,请根据材料回答以下问题)
    What are nitrates used for?
    A. They preserve flavor in packaged foods.
    B. They preserve the color of meats.
    C. They are the objects of research.
    D. They cause the animals to become fatter.



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  • ID:9121-14759

    In some countries, students are expected to be quiet and ________ in the classroom.

    A) skeptical B) faithful C) obedient D) subsidiary





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  • ID:9121-14758

    Hurricanes are killer winds, and their ________ power lies in the physical damage they can do.

    A) cumulative B) destructive C) turbulent D) prevalent




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