【推荐1】Before paper was invented, people wrote or drew on materials such as bamboo, silk, animal hide, and wooden blocks. Writing materials were     1     （real）expensive and few people learned to read. Therefore, few people wrote. This all changed, thanks     2     a man named Cai Lun.

Paper had already existed（存在）in China, but the process for     3    （produce）it was difficult and the paper was of low quality. Cai Lun began experimenting with many different materials and different     4     (method) to turn those materials into paper. In the year 105, he made it from tree bark, bamboo, cloth rags, and fishing nets. His paper was stronger and cheaper than any paper that had been made before.

People use umbrellas when it rains. However, the umbrella was not i    1     to keep off water when it rained. It was first used to keep off the sun.

N    2     knows who first invented it, but it was used long, long ago. At that time, in some places, ordinary people were not allowed to use the umbrella. In Europe, the Greeks were the f    3     to use the umbrella to keep off the sun. But the Romans were the first to use it to keep off rain. During the Middle Ages, people s    4     using the umbrella. Then it appeared again in Italy in the late sixteenth century. By 1680 the umbrella appeared in France and later on in England.

By the eighteenth century, the umbrella was used a    5     rain all over Europe. Umbrellas have not changed much in s    6     during all this time though they have become much lighter in weight.

In the twentieth century, women’s umbrellas began to be made in all k    7     of colors.

Many people get a lot of their news online or from newspapers and so on. But now more technology     1    （change）the way we get our news.     2    （Recent）, a new technology     3     can greatly influence the way we get the news, AI news presenters（主持人）, has started.

According     4     China's Xinhua News Agency, it said machine learning     5    （use）to examine video pictures and sounds of the two newsmen. One was able     6    （present）news in English, the other, in Putonghua.

Xinhua said the AI presenters would be     7     great change to the news team,     8     they “can work 24 hours a day" on its website and on social media, and they could read the news as     9    （natural）as human presenters.

Some scientists said the system showed China's latest progress in the Al area. But several scientists thought that "AI" does not correctly describe     10    （ability）of the robotic news presenters.

【推荐2】The third long March-5 rocket, China’s largest carrier rocket was     1    (success) launched(发射) from Wenchang Space Launch Center in Hainan Province on Dec. 27, 2019. The rocket     2    (name) Long March-5 Y3. It left the ground from the launch center at 8:45 p.m., carrying the Shijian-20 satellite, the     3    (heavy) and most modern communications satellite of China. About 2,220 seconds later, the satellite was sent into its     4    (plan) orbit(轨道).

The Long March-5 rocket made its first flight on Nov. 3, 2016 from Wenchang. However, the     5    (two) largest rocket, Long March-5 Y2, experienced a failure on July 2, 2017.     6    (compare) with Long March-5 Y2, the new rocket Long March-5 Y3 has shown more than 200 technological improvements.

Qu Yiguang, director of the Long March-5 Y3 research team, said, “Under great pressure, the research team has put all the efforts into the rocket over the past two years. We are very     7    (pride) that we can take part in the development of the Long March-5 rocket, which shows the highest level of China’s rocket technology.” After over two years of     8    (silent) in Wenchang, the Chinese welcomed the return of the “king” with excitement.

Since the Long March-1 sent China’s first satellite into space 50 years ago, the Long March series rockets     9    (complete) 323 flights. Over the past years, China’s rocket technology has been greatly improved. With the success of the Long March-5 Y3 rocket, China     10    (see) a busy year in space activities next year.