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    B A light bulb is a common device that we use to light up a room. Light bulbs change electricity into light. Every light bulb has six important parts. The first part, at the bottom of the light bulb, is the contactpoint. Electricity is brought into the light bulb from the contact point. The second part of the light bulb is the metal base. The metal base holds the light bulb in the lamp. The third part of the light bulb is the conducting wires.There are two wires. There conducting wires carry, or conduct, the electricity into the light bulb. The tungsten cord is the fourth part of the light bulb. It is in the middle of the bulb. Tungsten, T-U-N-G-S-T-E-N, is a kind of metal that can become very hot. This tungsten cord is the part of the light bulb that produces the light. The fifth part of the light bulb is also very important. This is the gas. The light bulb contains two gases: nitrogen and argon.these gases are used so that the tungsten cord does not melt even though the inside of the light bulb becomes very hot. The sixth part of the light bulb is the most obviouspart. That is the glass covering. The glass covering is of course necessary to keep the gas inside of the light bulb. If the glass covering breaks, the gas inside will go out and the light bulb won’t work. If the gas escapes, the tungsten cord will quickly burn out. 46． A light bulb is made of part. A. five B. six C. seven D. eight 47. What does the tungsten cord do in the light bulb? A. It protects gases from going out. B. It brings electricity into the light bulb. C. It protects the light. D. It holds the light bulb in the lamp. 48. What will happen if the gas escapes? A. The glass covering will break. B. The tungsten cord will become cool. C. The conducting wires will burn out. D. The tungsten cord will burn out. 49. The purpose of using a light bulb is . A. to made chemistry experiments B. to made physics experiments C. to cook food D. to light up the room 50. The glass covering of a light bulb is used to . A. give more light B. change electricity into light C. make the gas stay inside D. keep the gas inside the bulb burn 【查看更多】

     

    题目列表(包括答案和解析)

    短文填空

    阅读下面对话，根据对话内容在后面的划线处填一个适当的单词，每空一词。

    　　A: What can you see in the picture?

    　　B: I can see a bed, a desk and two chairs, a light(灯)and some books.

    　　A: Where are these things?

    　　B: They are in the bedroom.

    　　A: What's on the desk?

    　　B: A light and some books.

    　　A: Where are the chairs?

    　　B: They are behind the desk.

    　　A: And what's on the wall?

    　　B: Oh, it's a photo of Peter's family.

    　　A: Who's that?

    　　B: That's Peter's father and this is Peter's mother.

    　　A: Where is Peter's cat?

    　　B: Sorry, I don't know and I don't know its name.

    　　This is a picture of 1．   . I can see 2．   bed, a desk and 3．   chairs, 4．   light and some 5．   The 6．   is on the desk. Where are the 7．   ? They are on the desk, too. The 8．   are behind the desks. A picture 9．   Peter's family is on the 10．   . Peter's father and mother 11．   in the photo. We can't 12．   Peter's cat.  We 13．   know 14．   name.

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    听短文。根据所听内容选择正确的答案。短文读两遍。
    1. In the past, most Chinese people had _____ at night.
    A. a big meal
    B. a light supper
    C. a big supper
    2. Why is takeaway food popular in big cities of China?
    A. Because people don't want to cook for themselves.
    B. Because takeaway food is very cheap.
    C. Because people don't have enough time to cook for themselves.
    3. Where do many people have their lunch now in big cities?
    A. At homes.
    B. In restaurants.
    C. In their work places.
    4. When do many people have time for a big meal on weekdays?
    A. In the evening
    B. At noon.
    C. In the morning
    5. In which part of China can you find dumplings and noodles on the table?
    A. In the southern part.
    B. In the western part.
    C. In the northern part.

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    阅读理解。
           A man loses a needle in the room. He looks for it on the floor, but it is
    too dark in the room and he can’t see it. He comes out and looks for the
    needle in the street. A friend comes up.
         “What are you doing here?” he asks.
         “I los a needle, and I am looking for it now.” says the man.
         “ Where do you lose it?” he asks.
         “I lose it in my room.” says the man.
         “ You lose your noodle in your room, but you look for it in the street!
    Isn’t that funny?”
         “Ah,” says the man, “But it is very dark in my room. I can’t find it
    there. And here in the street is brighter and I can see it.” 
    1. The man loses ____________ in the room.
    A. his pen          
    B. a light          
    C. a needle        
    D. his glasses
    2. The needle is ___________now.
    A. in the street      
    B. on the road        
    C. in his pocket    
    D. in the room
    3. His friend thinks the man is __________.
    A. foolish          
    B. clever            
    C. lovely        
    D. smart
    4. The man looks for the needle in the street because ___________.
    A. he loses it in the street.          
    B. it’s dark in the room
    C. the needle is in the street          
    D. the needle is not in the room 
    5. The man can find the needle ____________.
    A. in the street      
    B. in his pocket      
    C. in the room      
    D. everywhere

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    You can’t see any object unless light from that object gets into your eyes．Some of the things you see give off light of their own。The sun，the stars，a lighted lamp are the examples that can be seen by their own light．But most of the things you see are not giving off light of their own．They are just reflecting(反射)light that falls on them from the sun or some other luminous bodies．The moon，for example，doesn’t give off any light of its own．It is not 1uminous．You see it because sunlight falls on it and some of the sunlight reflects on the earth．So moonlight is only second—hand sunlight．

        When you look at a book，it sends some of the light which fails on it to your eyes，and you see the book．If light could be kept out from where you’re so that there would be no light from the book to reflect．Then you couldn’t see the book even with your eyes wide open．Light travels so fast that the time in which it travels from the book you’re reading to your eyes is as short as if there were no time at time．Light reaches us from the moon，which is about 380，000 kilometres away，in only a little more than a second．

    1.You can see the book because________．

         A．your eyes are close to it       B．it reflects some of the light

         C．it has light of its own         D．it is big enough to be seen

    2.The Chinese meaning of the world“luminous”is close to_______．

         A．闪光的       B．看不见的      C．发光的       D．明亮的

    3.________has light of its own．

    A．The moon   B．The earth   C．The sun    D．The satellite of Dong Fong Hong

    4.Light travels about_________kilometers per second．

        A．300，000      B．100，000      C．400，000        D．190，000

    5.Which of the following is TRUE?

        A．All the things you can see give off light．

        B．Light from the book is much faster than that from the moon．

        C．The moment you open your eyes，the light from the book travels to your eyes．

        D．Light travels so fast that there is no time for you to read．

     

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    I am a writer. My job is to write something for the newspaper. I work very hard. Every morning I get up at seven. I take some exercise and then have a light breakfast. Then I drive to my office. It takes me thirty minutes, so I usually get there earlier than others.

    I am very busy. I think every minute counts, so I plan my work very carefully. I keep a diary to help me remember things. I meet and talk with many people. I make lots of telephone calls. I often go out and visit many people. I come back home at seven. I often watch TV at supper time. Then I begin to write down what I know. I like being busy.

    1.What does the writer of the passage think of his job?

    A．He hates (讨厌) it

    B．He likes it very much

    C．He feels it too tiresome (烦人)

    D．He doesn’t like it at all.

    2.The sentence “every minute counts” means ___________.

    A．合计

    B．数量

    C．计算出

    D．每分每秒都很重要

    3.How does he go to his office?

    A．By car

    B．By bike

    C．By bus

    D．By train

    4.Why does he often go out? Because __________.

    A．he wants to visit some friends

    B．he wants to make friends with others

    C．he wants to have some interviews (采访)

    D．he wants to ask for some stories

    5.What is the best title of the passage?

    A．My Busy Day

    B．How Busy I am

    C．Do You Want to be a Writer

    D．My Job

     

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