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    A. delay doing:延误.推迟做-- 【查看更多】

     

    题目列表(包括答案和解析)

     The doctors must get there in half an hour. There should be no____ in sending the blood to the dying girl .

    A. delay 　                B. wait              C. time 　       D.hurry

     

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    阅读理解

    　　In the atmosphere, carbon dioxide acts rather like a one-way mirror or the glass in the roof of a greenhouse which allows the sun's rays to enter but prevents the heat from escaping．

    　　According to a weather expert' s prediction, the atmosphere will be 3℃warmer in the year 2050 than it is today, if man continues to burn fuels at the present rate．If this warming up took place, the ice caps in the poles would begin to melt, thus raising sea level several metres and severely flooding coastal cities．Also, the increase in atmospheric temperature would lead to great changes in the climate of the northern hemisphere(北半球), possibly resulting in an alteration of the earth's chief food growing zones．

    　　In the past, concern about a man-made warming of the earth has concentrated on the Arctic because the Antarctic is much colder and has a much thicker ice sheet．But the weather experts are now paying more attention to West Antarctic, which may be affected by only a few degrees of warming, in other words, by a warming on the scale that will possibly take place in the next fifty years from the burning of fuels．

    　　Satellite pictures show that large areas of Antarctic ice are already disappearing．The evidence available suggests that a warming has taken place．This fits the theory that carbon dioxide warms the earth．

    　　However, most of the fuel is burnt in the northern hemisphere, where temperatures seem to be falling．Scientists conclude , therefore, that up to now natural influences on the weather have gone beyond those caused by man．The question is：Which natural cause has most effect on the weather?

    　　One possibility is the variable behavior of the sun．Astronomers at one research station have studied the hot spots and "cold" spots(that is, the relatively less hot spots)on the sun．As the sun rotates(使旋转), every 27.5 days, it presents hotter or "colder" faces to the earth, and different aspects to different parts of the earth．This seems to have a considerable effect on the distribution of the earth's atmospheric pressure, and consequently on wind circulation．The sun is also changeable over a long term：its heat output goes up and down in cycles, the latest trend being downward．

    　　Scientists are now finding shared relations between models of solar weather interactions and the actual climate over many thousands of years, including the last Ice Age．The problem is that the models are predicting that the world should be entering a new Ice Age and it is not．One way of solving this theoretical difficulty is to assume a delay of thousands of years while the solar effects overcome the inertia(惯性)of the earth's climate．If this is right, the warming effect of carbon dioxide might thus be serving as a useful opposed balance to the sun's fading heat．

    (1)

    It can be concluded that a concentration of carbon dioxide in the atmosphere would ________．

    [　　]

    A．

    mean a warming-up in the Antarctic

    B．

    raise the temperature of the earth' s surface

    C．

    prevent the sun's rays from reaching the earth's surface

    D．

    explain the cause of great changes in the climate in the northern hemisphere

    (2)

    The article was written to explain ________．

    [　　]

    A．

    the greenhouse effect

    B．

    the solar effects on the earth

    C．

    the causes affecting weather

    D．

    the models of solar-weather interactions

    (3)

    Although the fuel consumption is greater in the northern hemisphere, temperatures there seem to be falling．This is ________．

    [　　]

    A．

    mainly because the levels of carbon dioxide are rising

    B．

    partly due to changes in the output of solar energy

    C．

    possibly because the ice caps in the poles are melting

    D．

    only due to the effect of the inertia of the earth' s climate

    (4)

    On the basis of their models, scientists believe the opinion that ________．

    [　　]

    A．

    the climate of the world should be becoming cooler

    B．

    the new Ice Age will be delayed by the greenhouse effect

    C．

    the man-made warming effect helps to increase the solar effects

    D．

    it will take thousands of years for the inertia of the earth's climate to take effect

    (5)

    If the assumption about the delay of a new Ice age is correct, ________．

    [　　]

    A．

    ice would soon cover the northern hemisphere

    B．

    the greenhouse effect could work in favor of the earth

    C．

    the best way to overcome the cooling effect would be to burn more fuels

    D．

    the increased levels of carbon dioxide in the atmosphere could warm up the earth even more quickly

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    Half a century ago, during the Sino-Japanese War, I was a student at National Southwest Associated University at Kunming in southern China, Lectures were often accompanied by the pitter-patter of rain on the tin roofs of the classrooms; that mud floors were full of holes; and wind blew through paneless windows. As for the library, it was a bare skeleton. A good reference book was used for years and journals usually arrived after a couple of years’ delay.

        But despite such hardship, I had the best of my student days in Kunming. Although we were short of research materials, we were uncompromising（坚定的）in our pursue of knowledge and truth. I spent six years at Southwest and obtained my first and second degrees in physics here. I still value those days fervently. In fact it was at Southwest that I first came across Reader’s Digest. To me, the magazine’s insistence on perfection both in style and accuracy—as well as its celebration of life even in the face of hardship—is similar to the values I learned at Southwest.

        Later, I went to the United States to study under Enrich Ferimi, the famous physicist who directed the world’s first nuclear chain reaction. One of the first things Ferimi emphasized to me was that physics shouldn’t be so overwhelming（压倒性的）that it is beyond the average man. Physics research, he said, should be connected with our daily lives and physicists should devote most of their efforts to solving practical problems. I couldn’t agree more. Indeed, I think this simple, close-to-life.

        Approach applies other attempts too. Reader’s Digest is highly informative, but it is easy to read, and easy to understand, never exaggerating or mystifying. This truthful, down-to earth quality is what I treasure now.

    What is the author?

        A．A soldier    B．A teacher    C．An editor    D． A physicist

    Which of the following is NOT true of the National Southwest Associated University?

        A．The mud floors of the classrooms were uneven.    B．Its classroom windows had no glass.

        C．The only thing its library had was a skeleton.

        D．It was short of research materials.

    What was the first thing Ferimi emphasized to the author?

        A．Physics research should be related to daily lives.

        B．Physics should not be considered as the most important course.

        C.  Theoretical problems need solving first.

    D．The results of physics research could be used in the national defense.

    What does the author think of Reader’s Digest?

        A．It is far from perfect in style or accuracy.

        B．It devotes its efforts to solving practical problems.

        C．It gives much information.

        D．Its language is simple, but beautifully written.

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    The bad weather meant__________ the rocket launch(发射)for 48 hours,．

    A.delaying                       B．having delayed 

    C.to delay                       D．to have delayed

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    The bad weather meant__________ the rocket launch or 48 hours,．

    A.delaying                       B．having delayed 

    C.to delay                       D．to have delayed

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