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1. a hundred years
2. not new
3. a place where different treasures are kept and may be seen by visitors
4. human beings
5. a purpose for which something may be employed
6. long about things and….. about people
7. the meaning of the mark “A”
8. not wrong and not left
Text 4
Have you ever heard about Alan Turing? Read the text to find out about him and his work.
Alan Turing
Alan Turing was born in 1912 in London. He studied mathematics at Cambridge University. In 1937, he wrote a report which talked about a Turing Machine. This was a machine that could read programs and follow any number of instructions. It was only an idea, andhe did not have plans to build the machine, but his 1937 report was very important in the history of computing.
In 1939, Turing began to work for the British Government. During the Second World War (1939-1945), the Germans often sent messages from one group of soldiers to another. These messages gave important information and instructions, so of course they were secret. Although the British could get the messages, at first they could not understand them because they were written in a secret code. Turing began working on a computer to break this code.
Turing worked with other mathematicians at a secret place called Bletchley Park. They knew that the Germans were using machines called Enigma machines to send messages in code. To read and understand these messages you had to have another Enigma machine -and, of course, only the Germans had these.
Turing and the other people at Bletchley built a machine called the Bombe. (Some Polish mathematicians had already built a machine called Bombe to try to break the Enigma code. They worked with the British to build a new and better machine.) By 1942, the workers at Bletchley Park could read and understand all the German messages which used the Enigma code.
In 1943, the Germans started using a different code. The British called this code 'Fish'. It was much more difficult to understand than the Enigma code. The Bombe machine could not break this code, so the workers at Bletchley Park needed a new computer. In one year, they built Colossus. This was one of the world's first electronic computers which could read and understand programs.
Colossus got its name because of its size: it was as big as a room. It was able to understand difficult codes because it could do thousands of calculations every second. Without Colossus, it took three people six weeks to understand a message written in the 'Fish' code; using Colossus, the British needed only two hours to understand it. A modern PC from the year 2000 cannot do the work any faster.
Ex.1 Are these sentences true (T) or false (F)?
1. In 1937 A. Turing had a plan to build Turing machine.
2. Alan Turing and other mathematicians worked for the German government during the Second World War.
3. The British could get the messages sent by the Germans.
4. Bletchley began working in a computer to break German code.
5. The Germans had a machine called “Fish”.
6. Colossus was a very small computer.
7. Colossus helped the British to break the German code in two hours.
8. Colossus could read programs but couldn`t understand them.
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