Bing Dwen Dwen, the mascot (吉祥物) of the Beijing Winter Olympics, is a cute panda whose     1     (外形) is full-body “shell” made out of ice. It has     2     (使留下深刻印象) people with its wonderfully     3     (生动的) appearance and become popular in China.

Have you ever wondered why it is called Bing Dwen Dwen? In Mandarin (普通话) bing has several meanings, though the most common is “ice”. The character also symbolizes purity (纯洁) and strength, while dwen dwen means “strong and lively”.

Do you know why the mascot wasn’t named Bing Dundun in English? To read Bing Dundun correctly, you would have to be familiar with the pinyin system, which is       4     (难懂的) for foreigners, or the resulting pronunciation would be       5     (与……大不相同) the Chinese pronunciation. Moreover, “dun” is a word in English meaning “to ask someone to pay what they owe you again and again”. It also means “a dull greyish-brown color”. Both meanings don’t show goodwill. So, the Chinese Olympic Committee decided to change the name in an entirely new way.

There are some immediate advantages. The biggest is that the tone has been mixed into the spelling of each syllable (音节). The transliteration (音译) of Bing Dwen Dwen this time does work and is     6     (值得做的). It     7     (确保) foreign athletes and fans call Dwen Dwen “d-when d-when”, which is as close to the original “doon-doon” as an average English speaker can get.

In January, eight gorillas (大猩猩) at the San Diego Zoo Safari Park, in California, became the first great apes to test positive (阳性的) for COVID-19. “There was an immediate concern,” said Nadine Lamberski, the chief     1     (保护) and wildlife health officer at the San Diego Zoo Wildlife Alliance. “We want to     2     (尽我们的职责) and take all measures to make sure that won’t happen again.”

So Lamberski made a decision. In February, she gave nine other great apes an experimental COVID-19 vaccine. Those nine became the first zoo animals in the United States to get the vaccine. Since then, the vaccine has been shipped out to zoo animals in 27 states. Lamberski got the COVID-19 vaccine from Zoetis, a company that makes medications for animals. Now the company reports that its vaccine is safe for other animals, too. It’s     3     (incredible) wonderful news for animals and those who care about them.

So far, Zoetis has donated its vaccine to nearly 70 zoos in the U.S. According to Lamberski, zoos are requesting the vaccine because their animals     4     (受到……的威胁) getting the virus from visitors and caretakers. “Animals in zoos are exposed to hundreds, if not thousands, of people a day,” Lamberski said.

No matter how exciting space exploration sounds, there’s an important point that needs to be considered: food supplies. Right now, astronauts typically       1     (依赖) dry food in airtight bags and cans, since there are strict weight limits on items taken into space. Foods that we     2     (认为是理所当然的), such as fresh fruit and vegetables, are out of the question for space explorers.

For those who     3     (有强烈的愿望) to grow food during space flights, they’ve faced many difficulties, including the absence of gravity, and a lack of soil, air and humidity (湿度). However, growing food to add and minimize the food that must be carried to space will be increasingly important on long-duration flights into space. Recently, a leading team has worked out how plants can absorb nutrients from human urine (尿). Human urine is 95 percent water, with the other 5 percent    4     (构成；组成) nutrients which are harmful to the human body but not to plants, and it could supply three to four out of the six nutrients that plants need. By recycling liquid waste and producing food, an efficient cycle will be created.

And most importantly, the duration of space flights will be greatly extended to “20 years of flight”, meaning we may be soon sending astronauts on flights to Mars, or even beyond.

Are we a    1    ? What’s out there ?” Looking up at the s    2     , people have always wanted to l    3    more about space , and scientists work h     4    to find answers . They m    5     vehicles to carry b     6     people into space to find out the s    7     of the universe.They also really wish to d    8     other planets that are s    9    enough to s    10     life .

With the quick spread of COVID-19, more and more people around us are tested p    1    and people grow more and more     2    (焦虑). Here are some effective measures to p    3    you from being infected(感染)with the virus.

First, wear masks wherever you go, though it is not c    4    for you to perform daily routine. Second, m     5    distance from others. It is of extreme importance to avoid direct c    6    with those who have fever, cough or other COVID-19 symptoms(症状). Third, eat properly to ensure you have enough     7    (营养). If you have to eat outside, bringing food from home is     8    (推荐). Last but not least, we should a    9    importance to rest and exercise, which can help you     10    (恢复)sooner if you should fall ill.

Artificial intelligence aims to create intelligent machines. To achieve the aim, many approaches to     1    (create) true AI have been put forward. The dream of AI     2    has been around for centuries has finally become a reality. Nowadays, AI is already being applied in many fields. From autonomous vehicles to domestic robots, from     3    (recommend) systems to computers writing novels, AI has     4    unlimited number of applications. The technology     5    (transform) the way we live. However, the question is, where will all this lead?    6    we become more and more dependent on computers, some scientists are urging us to think about the dangers     7    (pose) by the advances in AI. Stephen Hawking, for example,    8    (warn), “The development of full artificial intelligence could spell the end of the human race.”     9    (apparent), such warnings demand our attention. We need to make sure that we will not fall victim     10    AI.