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    Everything more on the earth than on the moon because of gravity. 【查看更多】

     

    题目列表(包括答案和解析)

    阅读短文，然后根据短文内容选择最佳答案。

    　　We have always been interested in the moon．2000 years ago people already knew it moved around the earth and where it would be in the sky at different times of the year．At that time, everything about the moon was learned by watching it carefully in the sky．

    　　When scientists could use telescopes to study the moon more closely, their ideas began to change．They could see the moon was made of rocks．Most scientists thought moon rocks would be different from those on Earth．This was because they believed the moon had once been a planet that had been caught in the earth’s gravity(引力)millions of years earlier．

    　　In 1969 moon rocks were finally brought to the earth and studied．Much to their surprise, scientists found that, except for water, the moon and the earth were made of the same things．Once again new ideas were needed for this new information．

    　　After years of study, most scientists now think that the moon was once part of Earth．They believe very early in its history, maybe 4 million years ago, something about the size of Mars hit Earth．This sent billions of rocks into space around our planet．These rocks slowly joined together and after many years became the moon．

    　　In the future, even though our ideas about the moon may change again, we will still be interested in it．

    (1)

    What does the writer want to tell us in the passage?

    [　　]

    A．

    Why people are interested in the moon．

    B．

    How ideas about the moon have changed over time．

    C．

    Where the moon came from in the past．

    D．

    That people have finally learned the truth about the moon．

    (2)

    Before 1969 most scientists thought the moon was ________．

    [　　]

    A．

    part of the earth billions of years earlier

    B．

    older than the earth

    C．

    a planet caught by the earth’s gravity

    D．

    made of the same things as the earth

    (3)

    From this passage we can learn that ________．

    [　　]

    A．

    scientists in the past were not clever

    B．

    the earth was once part of the moon

    C．

    new information brings new ideas

    D．

    we now know everything about the moon

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    阅读下文，从所给的四个选项中选出一个最佳答案。
            We have always been interested in the moon. 2000 years ago people already knew it moved around the
    earth and where it would be in the sky at different times of the year. At that time, everything about the moon
    was learned by watching it carefully in the sky. 　　
            When scientists could use telescopes to study the moon more closely, their ideas began to change. They
    could see the moon was made of rocks. Most scientists thought moon rocks would be different from those on
    Earth. This was because they believed the moon had once been a planet that had been caught in the earth's
    gravity (引力) millions of years earlier. 　　
             In 1969 moon rocks were finally brought to the earth and studied. Much to their surprise, scientists
    found that, except for water, the moon and the earth were made of the same things. Once again new ideas
    were needed for this new information. 　　
             After years of study, most scientists now think that the moon was once part of Earth. They believe very
    early in its history, maybe 4 million years ago, something about the size of Mars hit Earth. This sent billions of
    rocks into space around our planet. These rocks slowly joined together and after many years became the moon.
    In the future, even though our ideas about the moon may change again, we will still be interested in it.
    1. Now, we're sure _________
    [     ]
    A. Moon rocks are quite different from those on Earth.
    B. Moon was once a part of Earth.
    C. Moon moves around Earth and it's the only satellite of Earth.
    D. Moon was once a planet caught in Earth's gravity.
    2. In 1969 there is a big event, that is __________.
    [     ]
    A. humans Found no water in Moon rocks
    B. scientists made out a modern spaceship
    C. scientists invented an advanced telescope
    D. humans left their footprints on Moon
    3. What does the writer want to tell us in the passage?
    [     ]
    A. Why people are interested in the moon.
    B. How ideas about the moon have changed over time.
    C. Where the moon came from in the past.
    D. That people have finally learned the truth about the moon.
    4. Before 1969 most scientists thought the moon was ________.
    [     ]
    A. part of the earth billions of years earlier
    B. older than the earth
    C. a planet caught by the earth's gravity
    D. made of the same things as the earth
    5. From this passage we can learn that ________.
    [     ]
    A. scientists in the past were not clever
    B. the earth was once part of the moon
    C. new information brings new ideas
    D. we now know everything about the moon

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    阅读理解。
         When you run downhill, gravity pulls you. When you throw a ball up, gravity pulls it down. When you
    sit, gravity holds you down. When you lie down, gravity holds you to the bed.
         We know gravity is everywhere even though we can't see it.We know it pulls on every stone and every
    drop of water. It pulls on everything.
         The gravity of the earth pulls everything towards the center of the earth.You know this when you try to
    lift a heavy stone. Gravity pulls it down. The more the stone weights, the more gravity pulls on it. To lift
    the stone, you must pull up harder than gravity pulls down. 
        The earth has gravity and the moon also has gravity. The moon has less gravity than the earth has. This
    means the moon's gravity does not pull as hard as the earth's gravity.
         Do you weigh 60 kilograms? That means the pull of the earth's gravity on you is 60 kilograms. If you
    were on the moon, you would weigh only 10 kilograms. The pull of the moon's gravity on you would be
    only 10 kilograms.
    1. The word "gravity" in the passage means "______" in Chinese.
    [     ]

    A. 物体质量
    B. 物体重量
    C. 万有引力
    D. 宇宙能量

    2. Gravity ______.
    [     ]
    A. pulls on everything high up
    B. is everywhere
    C. can be seen everywhere
    D. pushes on everything
    3. You can't lift up a big stone because ______.
    [     ]
    A. more gravity pulls it down
    B. you don't know how to do it
    C. you are not strong
    D. gravity is out of the stone
    4. If you weigh 50 kilograms, that means ______.
    [     ]
    A. you can lift up 50 kilograms of things
    B. the earth's gravity on you is less than 50 kilograms
    C. you can lift up more than 50 kilograms of things
    D. the earth's gravity on you is 50 kilograms
    5. If a stone weighs four kilograms on the moon, it weighs            .
    [     ]
    A. 10
    B. 24
    C. 40
    D. 60

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    请根据句意从方框中选择合适的动词，并用其适当时态填空，使句子通顺。

    weigh   break   have   draw   join   clap

    1．We've just come back from Hainan．We _________ a fantastic time there．

    2．Everything _________ more on the earth than on the moon because of gravity．

    3．--Where were you this time yesterday?

    --I _________ a picture in the park．

    4．The children _________ their hands excitedly as soon as the astronauts appeared on the stage．

    5．Good news! Our class _________ two school records so far!

    6．-- _________ Jim _________ in the next basketball match?

    --Of course he is．We can't win without him．

    查看答案和解析>>

        We have always been interested in the moon．2000 years ago people a1ready knew it moved around the earth and where it would be in the sky at different times of the year．At that time，everything about the moon was learned by watching it carefully in the sky．

        When scientists could use telescopes(望远镜)to study the moon more closely，their ideas began to change．They could see the moon was made of rocks．Most scientists thought moon rocks would be different from those on Earth．This was because they believed the moon had once been a planet(行星)that had been caught in the earth’s gravity(引力)millions of years earlier

        In 1969 moon rocks were finally brought to the earth and studied．Much to their surprise，scientists found that，except for water，the moon and the earth were made of the same thing．Once again new ideas were needed for this new information．

        After years of study，most scientists now think that the moon was once part of Earth．They believe very early in its history，maybe 4 million years ago，something about the size of Mars(火星)hit Earth．This sent billions of rocks into space around our planet．These rocks slowly joined together and after many years became the moon．

        In the future，even though our ideas about the moon may change again，we will still be interested in it．

    1．Now，we’re sure       

        A．Moon rocks are quite different from those on Earth．

        B．Moon was once a part of Earth．

        C．Moon moves around Earth and it's the only satellite of Earth．

    D．Moon was once a planet caught in Earth’s gravity．

    2．In 1969 there is a big event，that is       ．

        A．humans found no water in Moon rocks

        B．scientists made out a modern spaceship

        C．scientists invented an advanced telescope

    D，humans left their footprints on Moon

    3．What does the writer want to tell us in the passage?

        A．Why people are interested in the moon．

        B．How ideas about the moon have changed over time．

        C．Where the moon came from in the past．

        D．That people have finally learned the truth about the moon．

    4．Before l 969 most scientists thought the moon was        ．

        A．part of the earth billions of years earlier

        B．older than the earth

        C．a planet caught by the earth’s gravity

        D．made of the same things as the earth

    5．From this passage we can learn that          ．

        A．scientists in the past were not clever

        B．the earth was once part of the moon

        C．new information brings new ideas

        D．we now know everything about the moon

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