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    A．change B．to have changed C．to change D． to be changed 【查看更多】

     

    题目列表(包括答案和解析)

    -–I’d like to buy a new mobile phone．Mine isn’t popular.

    ---You’d better not since the mobile phones_____ so rapidly.

    　 A．have changed 　　　　　 B．will change 　　 C．are changing 　 D．were changed

     

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    Scientists have not come close to understanding all the different kinds of life on the planet, but US researcher Craig Venter is already working on creating the first artificial life.
    Venter and his researchers made a breakthrough this August. They successfully moved the DNA of one type of bacteria(细菌) to a yeast(酵母) cell, changed it, then put it into another bacterial cell.
    “Bacteria have systems that protect them from foreign DNA,” Venter explained to the BBC. In the experiment, the team managed to block this system.
    The experiment was performed on a simple type of bacteria called Mycoplasma mycoides. The team took the bacteria’s genes and put them into a yeast cell.
    Putting the DNA in a yeast cell allowed the team to change the genes----in this case, taking out a gene that was not necessary for the bacteria to live.
    They then put the gene into a host bacteria cell. The cell went on to divide normally, producing new healthy bacteria.
    In January, the team created artificial genes of a new type of bacteria. Their next goal is to put the artificial DNA into a host cell to create a new species, according to a report in Science magazine.
    “If we don’t make any errors, I think it should work and we should have the first artificial species by the end of the year,” Venter said in the report.
    The first artificial life from is likely to be a simple man-made bacteria, to prove that the technology can work. But that form will be followed by more complex bacteria that turn coal into cleaner natural gas, or algae that can take in carbon dioxide and change it into fuel.
    Many scientists think it’s good news to have this artificial life, but others are worried that the technology to create new organisms might end up in the wrong hands, with dangerous results.
    【小题1】Craig Venter and his team are working to ______.

    A．create a new animal
    B．clone a new species
    C．produce the first artificial bacteria
    D．develop a new system
    【小题2】Which of the following is the right order of the experiment?
    a. A gene was removed and put into a host bacteria cell.
    b. The genes were put into a yeast cell.
    c. The cell produced new healthy bacteria.
    d. The genes were changed.
    e. Some genes were taken out of Mycoplasma mycoides.
    A．d-e-a-c-bB．e-b-d-a-c
    C．a-d-e-c-bD．b-e-d-c-a
    【小题3】According to the passage, complex artificial bacteria, which will follow the first simple man-made bacteria, are intended to ______.
    A．cure deadly diseases
    B．prepare the Earth for natural disasters
    C．prove that the technology can work
    D．improve the earth’s environment
    【小题4】We can learn from the passage that ______.
    A．Venter and his team are the only scientists trying to create artificial life
    B．The experiment was based on research into different kinds of life on Earth
    C．A new type of bacteria was created in January
    D．All scientists are not in favor of the research

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    Michelle advised me not to change my mind easily, but the way of teaching I ________ greatly in the past six months．

    [　　]
    A．

    was used to have changed

    B．

    used to change

    C．

    used to changing

    D．

    was used to has changed

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    Reading comprehension．

    　　The challenge to drink to the limits of one’s endurance has become a celebrated part of college life．In one of the most extensive reports on college drinking thus far , a 1997Harvard School of Public Health study found that 43 percent of college students admitted binge drinking in the preceding two weeks (Defined as four drinks in a sitting for a woman and five for a man , a drinking binge is when one drinks enough to risk health and well - being)

    　　Experts estimate that excessive drinking is involved in thousands of student deaths a year．And the Harvard researchers found that there has been a dramatic change in why students drink 39 percent drank “to get drunk” in 1993 , but 52 percent had the same objective in 1997．

    　　“What has changed is the across - the - board acceptability of intoxication (喝醉) ,” says Felix Savino at UW - Madison．Many college students today see not just drinking but being drunk as their primary way of socializing”．

    　　The reason for the shift are complex and not fully understood．But researchers guess that it may have something to do with today’s instant - satisfaction life - style－－and young people tend to take into the extreme．

    　　While binge drinking isn’t always deadly , it does have other , wide - ranging effects．Academics is one area where it takes a heavy toll (something paid , lost or suffered)．Perhaps because alcohol increases aggression and affects judgment , it is also related to 25 percent of violent crimes and roughly 60 percent of vandalism on campus．Facing the many potential dangers; college campuses are searching for ways to reduce binge drinking．

    (1)

    Why has“binge drinking”caused widespread concern?

    [　　]

    A．

    Because it is directly responsible for the academic problem on campus．

    B．

    Because it has claimed many young lives every year．

    C．

    Because it has had harmful effects on the students’ health and well - being．

    D．

    Because it is in close connection with school violence．

    (2)

    We can infer from the passage that young people today ________．

    [　　]

    A．

    cherish their dream and are willing to work hard for it．

    B．

    value spiritual satisfaction over physical satisfaction．

    C．

    are idealistic and disillusioned by the stark reality．

    D．

    seek immediate satisfaction and indulge (放纵) themselves too much

    (3)

    The paragraphs following the passage most probably discuss ________．

    [　　]

    A．

    efforts taken by different schools to fight against binge drinking

    B．

    the importance of banning alcohol at student events on campus

    C．

    how to change students’ behavior

    D．

    the possible consequences of binge drinking

    (4)

    Students regard drinking and binge drinking as ________．

    [　　]

    A．

    tolerable

    B．

    acceptable

    C．

    necessary

    D．

    essential

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    The country life he was used to _______ greatly since 1992.

     A．change       B．has changed     C．changing      D．have changed

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