Have you ever heard the story of Internet? We are all busy     1    (talk) about and using the Internet, but how many of us know the history of the Internet?

Many people are     2    (surprise) when they find that the Internet was set up in the 1960s. At that time, computers were large and expensive. Computer network didn't work well. If one computer in the network broke down, then the whole network stopped. So a network system had to be set     3    . It should be good enough to be used     4     many different computers. If part of the network was not working, information could     5    (send) through another part. In this way computer network system would keep on     6    (work) all the time.

At first the Internet was only used by the government, but, in the early 1970s, universities, hospitals, and banks were allowed to use it, too. However, computers were still     7    (expensive) than they are and the Internet was difficult to use. By the start of the 1990s, computers became cheaper and easier     8     (use). Scientists had also     9    (develop) software that made “surfing” the Internet more convenient.

Today it is easy to get online and it is that millions of people use the Internet every day. Sending E-mail is more and more popular     10     students.

China     1    (launch) a national cloud learning platform since Feb.3 and started broadcasting primary school classes     2    (make) sure the country’s 180 million students can still keep learning even though schools are closed, according to state-run news agency Xinhua. A new school semester,    3    (schedule) to start today, has been postponed indefinitely as part of    4    (measure) to combat the coronavirus. China authorities have encouraged people to stay at home to help reduce    5    (it) spread.

The approach differs by age. Primary school classes are being broadcast on one of China’s state TV channels. Junior and senior high school students in China can use an online learning platform     6    has 169 lessons covering 12 subjects for the first week, based on the national curriculum. Teachers will keep     7    (update) the platform with new materials as needed.

The government has enlisted the China's three    8    (big) telecoms operators—China Mobile, China Unicom and China Telecom—plus tech companies like Huawei, Baidu and Alibaba to back up the platform with 90 terabytes of bandwidth and 7,000 servers,     9    (ensure) up to 50 million students can use it simultaneously, according to state broadcaster CCTV News. About 600,000 teachers have also been using a live streaming service called Dingtalk, built by Alibaba, to conduct online classes, the company said, although it has    10    (apparent) not gone down so well with many students.