We are all busy talking about and using the Internet (互联网), but how many of us know the h_______ of the Internet?
　　Many people are surprised when they find that the I____ was set up in the 1960s. At that time, computers were large and e_____ . Computer networks (网络) didn't work well. If one computer in the network broke down, then the whole network stopped. So a new network system had to be set up. It should be good e_____ to be used by many different computers. If part of the network was not working, information could be sent through a___ part. In this way computer network system would keep on w______ all the time.
　　At f__ the Internet was only used by the government, but, in the early 1970s, universities, hospitals and banks were allowed to use it too. H__, computers were still very expensive and the Internet was d____ to use. By the start of the 1990s, c___ became cheaper and easier to use. Scientists had also developed software that made 'surfing' (浏览) the Internet more convenient.
Today it is easy to get on-line (上网) and it is said that m____ of people use the Internet everyday. Sending e-mail is more and more p____ among students.
The Internet has now become one of the most important parts of people's life.