①Since the first man looked up at the flying birds, countless successes have been achieved on the way up to the sky. From the stones thrown into the air to airships of all kinds, pioneers of humans never failed to let their imagination run wild.

②Stories of pioneers go back to centuries ago.

③Kite flying in China dates back to the 5th century BC and is thought to be the earliest example of man-made flight.

④From the 3rd century BC, the sky lantern (灯笼) was known in China. Many people believe that it was invented by Zhuge Liang in the war. Some say he wrote a message on a sky lantern for help, while others believe sky lanterns were used to drive the enemies away.

⑤Whichever is true, humans have never stopped, and they never will. In modern times, new fields are being explored (探索).

⑥In 1993, the world’s largest hot air airship was built. The AS-300 carried an underslung raft (悬挂式木筏). It allowed a team of French scientists to carry out their treetop researches without too much harm to the rain forest.

⑦On May 15, 2022, Chinese scientists sent up the latest model of “Jimu No.1”, China’s self-developed airship, to collect weather information on the Qinghai-Tibet Plateau.

⑧The airship would work at a world-record altitude (海拔) of 9,032 meters. It was the first time an airship of its size had reached this height, even higher than that of the 8,849-meter-tall Mount Qomolangma, the highest mountain in the world.

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The sneakers have been our best friends and can go with us in walking, running, dancing and also in the other sports. They always give us a comfortable feel and good look when we wear them. These sneaker shoes have a fascinating history behind their evolution(演变).

The sneakers were first produced in the year of 1800 with a simple rubber sole(鞋底)design. The shoes were given the name sneakers because the soles were so soft and they did not make any sound on the ground. Keds was the first company during the early decades to produce the sneakers.

As time passed by, the sneakers also got the interest of teens and they became part of their fashion. Sneakers started ruling youngsters’ fashion world. Then the famous company, Nike, also entered the sneaker world. The Nike Tailwind was their first model of sneakers and it was followed by Air Jordan in the following years. Nike plays an important role in the production of sneaker shoes and they also have the top place in the athletic shoes’ market.

But now, sneakers can be given any possible shape according to a designer’s imagination. They are used as casual sneakers, dance sneakers and athletic sneakers suiting men and women. The Vans plays an important role in the production of sneakers for women. These sneakers play an important part in the fashion world and they come in different kinds of models and suit everybody’s need. Thus, sneakers, with a long history, have reached the top place in the market.

The launch of BeiDou Navigation Satellite System(北斗卫星导航系统) on June 23rd 2020 marks the completion of China’s self-developed and operated BeiDou network, one of the four global navigation networks, along with the USA’s GPS, Russia’s GLONASS and the European Union’s Galileo. It also marks the end of the country’s dependence on America for an important service: location data.

GPS was the earliest network to provide global location data. The system is owned by America’s government, which means American officials could decide to turn off or downgrade the signals coming from GPS satellites. The main purpose of building BDS is to give China full control over a navigation system.

Work on BDS began in the 1990s and included three phases. The first phase was about building the BeiDou-1 system, which started in 1994 and in 2000 provided positioning, short message telecommunication and timing services in China. The second phase-the BeiDou-2 system, which started in 2004, was completed in 2012. The BeiDou-2 ground system not only serves China but also provides users in the Asia-Pacific region with more than ten satellites and offered services above. The third phase involved the development of the BeiDou-3 system, which started in 2009 and was completed in June, 2020. As one of the IGE members, China is always cooperating with foreign countries and use BDS to serve global users with high performance and high quality in scientific research.

BeiDou’s satellites are more advanced than those of GPS. In the Asia-Pacific region, BeiDou claims a 10-cm accuracy, compared with 30 cm positioning without doing wrong offered by GPS. America began upgrading its system in 1997 but it may take another 15 years to finish the project.