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    If we are driving a car or crossing a street, we will stop when the traffic lights turn red. Why do we use red rather than other colors?
    As we know, scattering (散射) happens when light goes through the air. For the same media, if the wavelength (波长) is long, the scattering will be short. If the wavelength is short, then the scattering will be long.
    Of all light we can see red has the longest wavelength, so the scattering is the weakest. That means the red light travels far. In fact, it travels farther on rainy days.
    Using the red light can help drivers in farther areas see the lights. It helps drivers slow down or stop in time. If drivers don’t see the red light until they are close, they may not be able to stop the car in time. An accident may happen. Red can also excite people. We can act more quickly when we see the color red.
    In a word, red light helps drivers stop in time and help prevent accidents.
    【小题1】______ has the longest wavelength of all light we can see.
    A．RedB．GreenC．YellowD．Black
    【小题2】Red light travels farther on ______ days.
    A．windyB．sunnyC．rainyD．cloudy
    【小题3】Red can make people act more quickly because ____________.
    A．red can make people happierB．the scattering of red is very short
    C．the scattering of red is very longD．red can make people more excited
    【小题4】The underlined word “prevent” means ______ in Chinese.
    A．逃避B．防止C．处理D．检查
    【小题5】The passage mainly tells us ____________.
    A．why accidents happenB．how the red light travels
    C．why we use red traffic lightsD．how to stop in time at traffic lights

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    If we want to cut hair,we should go to         .

    A．the kichenB．the bathroomC．the barber shopD．the doctor’s

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    If we sit near _______ front of the bus, we’ll have _______ better view.

    A．不填; theB．不填; aC．the; aD．the; the

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    If we _________ our dreams, we believe one day our dreams will be________.
    A. hold on; achieved
    B. hold on to; come true
    C. hold on to; achieved

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    “If we don’t often wash our hands, we can pick up viruses（病毒）form many places and make ourselves ill,” a man from CDC says. Doctors always say every time when you touch your eyes, nose or mouth, you may be ill. In fact, one of the common（平常的） ways of catching a cold is by rubbing（擦拭）their noses or their eyes when there are viruses on their hands. If you don’t often wash your hands, especially when you’re sick, you may spread the viruses to others. You should wash your hands in these situations:
    1. After using the washroom
    2. After rubbing your nose or coughing.
    3. Before eating or making food.
    4. After touching animals.
    5. After visiting a sick man.
    6. When your hands are dirty.
    There’re right ways to wash your hands. Follow these things to keep your hands clean:
    1. Use warm water (not cold or hot).
    2. Wash for 15 seconds.
    3. Wash well under warm running water and dry them with a clean towel.
    阅读短文，填表格。
    Information Card

    A way to protect against the spread of illness
    		    1   
     
    Situations in which you must wash your hands
    		After using the   2 
    Before making   3 
    After visiting the   4  people
    A correct way to wash your hands
    		Use   5  running water
    Time needed to wash your hands
    		     6    

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