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    There are nine in the universe. 【查看更多】

     

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    根据所给提示，完成下面句子。

    There are nine ________(行星)in the universe．

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    The Sun's Family

    　　The earth is not the only body that travels around the sun. With it are eight other planets(行星), fellow members of the sun's family.

    　　Two of them are nearer while the other six are farther from the sun than the earth is. The farther they are, the longer trips they make around the sun. People noticed long ago that these made travelling bodies move around in the sky in definite(一定的) paths.

    　　We know that every little bit of matter in the universe pulls upon every other bit of matter. There exists(存在) a pull between the earth and the moon, which keeps the moon travelling in its orbit(轨道) around our planet, the earth. The gravity(重力) holds you to its surface, and pulls back to it the ball which you throw into the air. Of course the ball also pulls on the larger earth, but the earth is so much larger that the pull is not noticed.

    　　Now remember that large bodies exert (施加) a greater pull on any body than smaller ones which contain(含有) less material (原料，材料). But each object in the universe, no matter how small, pulls on all other objects to some degree(某种程度).

    1．According to the passage, there are ________ fellow members besides the earth in the sun's family.

    [　　]

    A．eight other
    B．seven other
    C．nine other
    D．over ten other

    2．Which of the following statements is TRUE?

    [　　]

    A．The earth is farther from the sun than any of the other eight planets.

    B．Two of the planets are farther from the sun than the earth.

    C．Six of the planets are closer to the sun than the earth.

    D．The earth is the third nearest planet to the sun.

    3．What holds the nine planets in their paths?

    [　　]

    A．The sun's energy(能量).
    B．The earth.
    C．The universe.
    D．Gravity.

    4．Why the moon travels around the earth is ________ .

    [　　]

    A．that the sun pulls upon the moon

    B．that the earth pulls upon the moon

    C．that the earth and the moon pull upon each other

    D．that the other eight planets pull upon the moon

    5．In the last paragraph the writer tell us ________ .

    [　　]

    A．each object in the universe pulls upon all the others more or less

    B．a large body pulls on a small one less than a small body pulls on a large one

    C．a small body does not pull on a large one

    D．the pull between two bodies is always equal(相等)

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    阅读理解(20分)

    　　Our sun is a star，and nine worlds move round it．Worlds like these are planets(行星)．

    　　But there are other stars，other suns．Not only thousands of them，but millions of them．Do different stars have planets？We can see the planets round our own sun．But we haven't seen any more．The stars are too far away from us．Stars give out(发出)light，but the planets don't have any light of their own．So we can't see them．They're too far，and too dark．

    　　Still，we can tell that some stars have planets．While a big planet goes round，it pulls its star to one side．And sometimes we can see this．Then we know that the star has a planet．

    　　For example，Barnard's Star(巴纳德星)is a small red star．And it is the quickest star in the universe．But sometimes it moves slower，and then quicker again．We have known Barnard's Star for many years，and now we are sure it has a planet．

    (1)

    A star is a large body in the universe．It ________．

    [　　]

    A．

    moves round our sun

    B．

    has light of its own

    C．

    can also be called a sun

    D．

    both B and C

    (2)

    Which of the following is not true？

    [　　]

    A．

    The earth is one of the sun's worlds．

    B．

    There are millions of suns in the universe．

    C．

    The worlds are very bright．

    D．

    Some stars have planets．

    (3)

    We can see the planets round our sun．But we can't see ________．

    [　　]

    A．

    nine worlds in the universe

    B．

    the planets round other stars

    C．

    the satellites round the earth

    D．

    other stars

    (4)

    Barnard's Star moves more quickly than ________．

    [　　]

    A．

    most stars

    B．

    any other star

    C．

    its planet

    D．

    the planets round the sun

    (5)

    How can people know that there is a planet round Barnard's Star？

    [　　]

    A．

    Sometimes they see that the planet pulls the star to one side and makes it move slower．

    B．

    The planet is shining．

    C．

    The planet is next to our earth．

    D．

    The planet is a red one．

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