单项选择题
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THE HISTORY OF THE INTERNET
Many people are surprised when they find that the Internet was{set up; set off; set forth}in the 1960s. At that time, computers were large and expensive. Computer network didn"t work well. If one computer in the network{broke out; broke through; broke down} , then the whole network stopped. So a new network system had to be set up. It should be good enough to be used by many different computers. If part of the network was not working, information could be sent through{another; the other; other}part. In this way computer network system would keep on working on the time.
At first the Internet was only used by the government, but in the early{nineteen seventy; 1970s; 1970}, universities，hospitals and banks were allowed to use it too. However, computers were still very expensive and the Internet was difficult to use. By the start of the 1990s, computers became{more expensive; smaller; cheaper}and easier to use. Scientists had also developed software that made “surfing” in the Internet more convenient.
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