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    Of all stars, sun is nearest to us. 【查看更多】

     

    题目列表(包括答案和解析)

    　　Light travels at a speed which is about a million times faster than the speed of sound. In a second, light travels about 300,000km, but sound travels only 340m. You can get some ideas of this difference by watching the start of a race. If you stand some distance away from the starter, you can see smoke come from his gun before the sound reaches your ears.

    　　This great speed of light produces some strange facts. Sunlight takes about 8 minutes to reach us. If you look at the light of the moon tonight, remember that the light rays left the moon 1.3 seconds before they reach you. The nearest star is so far away that the light which you can see from it tonight started to travel towards you four years ago at a speed of nearly 20 million km, per minute. In some cases, the light from one of tonight's stars started on its journey to you before you were born.

    　　Thus, if we want to be honest, we can not say,“the stars are shining tonight.”We have to say,“The stars look pretty. They were shining four years ago but their light has only just reached the earth.”

    　　阅读短文，选择最佳答案．

    (1) The speed of light is ________ than the speed of sound.

    [　　]

    A．a million times slower

    B．about millions of times faster

    C．about a million times faster

    (2) If you stand 200 meters away from a man who is firing a gun to start a race, you will find out that ________.

    [　　]

    A．you can hear the gun before you see the smoke

    B．sound doesn't travel as fast as light

    C．the sound of gun will reach you before the man fires his gun

    (3) Sunlight ________ to the earth than the light of the moon.

    [　　]

    A．has to travel a greater distance

    B．moves less quickly

    C．is less powerful

    (4) The scientific way of saying“the star are shining tonight”should be ________.

    [　　]

    A．the stars have been shining all the time

    B．the stars seen tonight will be shining four years later

    C．the stars were shining long ago but are seen tonight

    (5) The light of the nearest star you see tonight has been ________ for four years.

    [　　]

    A．away from the star

    B．on the moon

    C．away from the sun

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    阅读理解。
         There is nothing more important than the sun. Without the sun all living things(生物) on the earth will die.
         The sun is a star. In the sky there are thousands of stars like the sun. They are as large as the sun and as
    hot as the sun. At night you can see many stars, but in the daytime you can see only one star, the sun.
         The sun is much nearer to us than any other star. That is why it looks the biggest and the brightest of all
    the stars. The distance of the sun from the earth is as much as 150 million kilometers. Most of the stars are
    thousands of light years away from the earth.
         Do you know the light year? Nothing in the world travels faster than the light. It travels 300,000 kilometres
    a second (one-sixtieth of a minute). And one light year is the distance that light travels in one year.
    1. Without the sun, ___.
    A. some living things will live on the earth
    B. people can not live on the earth
    C. only some plants can live on the earth
    D. there will be no stars in the sky
    2. In the daytime you can only see the sun because _____.
    A. other stars are too far away
    B. there are no other stars in the sky
    C. the sun is the biggest in the sky
    D. the other stars only come out at night
    3. Why does the sun look the biggest and the brightest of all the stars?
    A. The sun is far away from the earth.
    B. The sun is the nearest star to the earth.
    C. The sun is 150 kilometres away from the earth.
    D. The sun is much bigger and brighter than other stars.
    4. Light travels _____.
    A. 300,000,000 kilometres a minute
    B. 300,000 metres a second
    C. 300,000,000 metres a second
    D. 3000,000 kilometres a minute
    5. "Light year" in this passage means _____.
    A. light
    B. year
    C. a far-away place
    D. a very, very long way

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    阅读理解

    　　Every night the stars seem to move slowly round the sky in a great circle(圆周)．But one star is different from others．It looks as if it never moved．To us, it is always in exactly the same place all thetime．It is called the Pole Star(北极星)．It is not a very bright star, but it is very important．Sailors use the Pole Star to find out where they are moving to．

    　　The amazing(令人惊奇的)thing is that the stars are all so far away．If you travelled in the spaceship for a hundred years you would still not reach the nearest star!

    　　A star is really a great ball of burning gas(燃烧的气体)，like the sun．Some stars are much bigger than the sun, But they are all so far away from us that they just look like dots(圆点)of light．

    　　On the clearest night you can count about 2 000 stars．This may seem a lot, but with a telescope you can see many more．The better the telescope, the more stars you can see．Scientists tell us there are millions and millions of stars．No one know exactly how many there are．

    　　根据短文内容选择最佳答案．

    (1)

    The stars ________．

    [　　]

    A．

    are not moving all the time

    B．

    seem to move slowly

    C．

    are moving slowly round the earth

    (2)

    A star is ________．

    [　　]

    A．

    a planet like the earth

    B．

    a ball of burning gas like the sun

    C．

    something called a“constellation(星座)”

    (3)

    The stars we see look like dots of light because ________．

    [　　]

    A．

    they are not very big

    B．

    there are lots of light on stars

    C．

    they are very far away

    (4)

    How many stars are there?

    [　　]

    A．

    Less than 2 000．

    B．

    No one knows exactly．

    C．

    Exactly 1 000 million．

    (5)

    The word“telescope”means ________．

    [　　]

    A．

    放大镜

    B．

    望远镜

    C．

    显微镜

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    阅读理解

    　　Every night the stars seem to move slowly round the sky in a great circle(圆周)．But one star is dif-ferent from others．It looks as if it never moved．To us, it is always in exactly the same place all thetime．It is called the Pole Star(北极星)．It is not a very bright star, but it is very important．Sailors use the Pole Star to find out where they are moving to．

    　　The amazing(令人惊奇的)thing is that the stars are all so far away．If you travelled in the space-ship for a hundred years you would still not reach the nearest star!

    　　A star is really a great ball of burning gas(燃烧的气体)，like the sun．Some stars are much bigger than the sun, But they are all so far away from us that they just look like dots(圆点)of light．

    　　On the clearest night you can count about 2 000 stars．This may seem a lot, but with a telescope you can see many more．The better the telescope, the more stars you can see．Scientists tell us there are millions and millions of stars．No one know exactly how many there are．

    根据短文内容选择最佳答案．

    (1)

    The stars ________．

    [　　]

    A．

    are not moving all the time

    B．

    seem to move slowly

    C．

    are moving slowly round the earth

    (2)

    A star is ________．

    [　　]

    A．

    a planet like the earth

    B．

    a ball of burning gas like the sun

    C．

    something called a“constellation(星座)”

    (3)

    The stars we see look like dots of light because ________．

    [　　]

    A．

    they are not very big

    B．

    there are lots of light on stars

    C．

    they are very far away

    (4)

    How many stars are there?

    [　　]

    A．

    Less than 2 000．

    B．

    No one knows exactly．

    C．

    Exactly 1 000 million．

    (5)

    The word“telescope”means ________．

    [　　]

    A．

    放大镜

    B．

    望远镜

    C．

    显微镜

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    完形填空

    　　The sun, the moon and the stars are all in the sky．The earth 　　1　　 round the sun．And the moon circles(围绕)the earth．

    　　The sun is 　　2　　 than the moon．It gives us light and heat(热量)．When our part of the earth turns 　　3　　 the sun, it is day．When our part of the earth turns away 　　4　　 the sun, it is night．“Morning”is the time 　　5　　 sunrise(日出)and twelve o'clock, the 　　6　　 is overhead(当头)．It is“noon”．And when the sun sets(日落), it is“evening”．

    　　The moon is much smaller than the sun．It 　　7　　 bigger only because it is much 　　8　　 the earth．It is our nearest neighbour(邻居)in space(宇宙)．Sometimes it looks quite bright, but it 　　9　　 any light at all．The light on the moon 　　10　　 from the sun．It only reflects(反射)the 　　11　　 of the sun．

    　　The stars look 　　12　　 than the sun and the moon．But 　　13　　 of the stars are bigger than the sun．　　14　　 look small because they are very far away from 　　15　　．

    (1)
    [　　]

    A．

    move

    B．

    moves

    C．

    is moving

    D．

    is going to move(移动)

    (2)
    [　　]

    A．

    big

    B．

    much big

    C．

    much bigger

    D．

    much more bigger

    (3)
    [　　]

    A．

    in

    B．

    into

    C．

    at

    D．

    to

    (4)
    [　　]

    A．

    from

    B．

    to

    C．

    into

    D．

    /

    (5)
    [　　]

    A．

    like

    B．

    between

    C．

    for

    D．

    in

    (6)
    [　　]

    A．

    earth

    B．

    moon

    C．

    sun

    D．

    star

    (7)
    [　　]

    A．

    is

    B．

    has

    C．

    looks

    D．

    likes

    (8)
    [　　]

    A．

    nearer

    B．

    near

    C．

    near to

    D．

    nearer to

    (9)
    [　　]

    A．

    doesn't give

    B．

    doesn't have

    C．

    gives

    D．

    has

    (10)
    [　　]

    A．

    come

    B．

    comes

    C．

    goes

    D．

    has

    (11)
    [　　]

    A．

    light

    B．

    lights

    C．

    heat

    D．

    night

    (12)
    [　　]

    A．

    small

    B．

    smaller

    C．

    big

    D．

    bigger

    (13)
    [　　]

    A．

    much

    B．

    some

    C．

    many

    D．

    most

    (14)
    [　　]

    A．

    It

    B．

    They

    C．

    Some

    D．

    All

    (15)
    [　　]

    A．

    It

    B．

    them

    C．

    us

    D．

    the sun

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