Question

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¡¡¡¡The world¡¯s first completely automatic(×Ô¶¯µÄ)railway has been built under the busy streets of London£®1£®________£®The new Victoria Line was opened in 1969£®This new line was very different from the others£®

¡¡¡¡The stations on the other lines need a lot of workers to sell tickets, and to check and to collect them when people leave the trains£®2£®________£®Here a machine checks and collects the tickets, and there are no workers on the platforms at all£®On the train, there is only one worker£®3£®________£®But usually he just starts it; it runs and stops by itself£®The trains are controlled by electrical signals which are sent by the so-called command spots£®The command spots are the same distance apart£®Each sends a certain signal£®The train always moves at the speed that the command spots allow£®If the command spot sends no signals, the train will stop£®4£®________£®The computers also fix the train speeds, and send the signals to the command spots£®

¡¡¡¡5£®________£®Once train may stay too long at a station; the other trains will then automatically move slower£®

A£®If necessary, this man can drive the train£®

B£®The railway is called the Victoria Line, and it is part of the complete London underground railway£®

C£®The computer makes the decision about when to use a gas engine and when to go electric£®

D£®This is all different on the Victoria Line£®

E£®Most of the control work is done by computers£®

F£®Other machines make sure that the trains are always a safe distance apart£®

Answer 1

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