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.

The Chinese Spring Festival is    1     (一个全家团聚的特殊时刻). But     2    (2020年的春节不一样, 在此期间, 全家人都要待在家里). We could not go out to pay a visit to our relatives or     3    (去人多的地方).     4     (我们这样做是因为中国发生了新冠肺炎). To fight against the virus,    5     (我们必须待在家里, 家里更安全).

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.