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    Do you know how to o on the machine? 【查看更多】

     

    题目列表(包括答案和解析)

    据汉意或首字母的提示，填写所缺的单词。
    1. Yesterday I______ (睡过头了), I was late for school.
    2. Alexander Graham Bell i______ the telephone in 1876.
    3. Do you know how to o______ on the machine?
    4. Have you b_____ the baby's milk yet?
    5. The doctor didn't ______ (披露) the truth to him.

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    阅读理解。
        David's got a text message from his friend Sam. Can you understand it?
        7,15      20,15      20,8,5      16,1,18,11
        This message was in code (密码, 代码). How many letters are there in the English alphabet?
    Twenty-six. So can you read it now?
    A   B   C   D  E   F   G  H   I    J  K L M N O P Q R S T U ...
    1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 ...
        David decided to use a different code in his answer to Sam. This time, he was putting A instead of B,
    B instead of C, and so on. His message to Sam shown on the right was very short. Can you understand?
    A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
    B C D E F G H I J K L M N O P Q R S T U V W X Y Z A
        Sam guessed David's code, and he replied: ZESDQ, RBGNNK. When David's little sister saw the message,
    she felt puzzled. She couldn't read it at all. But David was very happy that his sister couldn't read his message!
         Lots of people use codes to send secret messages. In a war, secrets are very important so soldiers often
    send each other messages in code. Nowadays, we can use computers to make and break difficult codes. Even
    before computers, people invented other machines to do this. 
        Here's a famous machine that Germans used in the Second World War (1941-1945). It's called the Enigma
    Machine. The machines were very big, heavy and expensive. Every day they changed the codes automatically,
    and this made it almost impossible for anyone to break the codes. The person sending a message had one
    machine, and the person receiving the message had another.  
    1．Sam asked David to go to the ______.
    [     ]
    A．park
    B．house
    C．museum
    D．zoo
    2．Sam told David to meet him ______.
    [     ]
    A．before breakfast
    B．after school
    C．after dinner
    D．before school
    3．Codes are used to keep something ______.
    [     ]
    A．new
    B．old
    C．secret
    D．known
    4．People will never know the meaning if they can't ______ the code.
    [     ]
    A．break
    B．make
    C．change
    D．write
    5．The best title of this passage is           .
    [     ]
    A．English Letters
    B．Codes
    C．Messages
    D．Machines

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