1 . Somebody is calling for help in the water. You want to jump in and save them, but that might put you in danger. What do you do?

Soon this won’t be a problem anymore because a robot swimmer called Swumanoid will be on hand to help.

Scientists from Japan designed this robot to swim like an Olympic athlete (运动员). They mapped a swimmer’s body and looked at how every part of the body moves while swimming. The robot can swim just like a human does.

Swumanoid can swim the backstroke (仰泳) and the front crawl (自由泳) at a speed of 0.64 meters a second, about one-third of the world record speed for these swimming styles, according to the Daily Mail.

Motomu Nakashima, head of the team that designed the robot, hopes that robots like Swumanoid can serve as lifeguards in the future.

Besides saving lives, Swumanoid can also be used in swimming research. It can test water resistance, which makes it move more slowly. And it helps to find out how people swim. The information that is collected could help scientists find ways to improve a swimmer’s skills.

Unlike human swimmers, robots don’t get tired from doing the same stroke (泳姿) again and again, so they do not slow down. Therefore, they can collect information more efficiently (有效地).

But the robot is not yet ready to take the place of human lifeguards. Scientists say there are still certain things that need to be improved, such as its motors (引擎) and waterproofing design (防水设计).

3 . You may think you cannot live through summer without air conditioners （空调）. But in ancient China, hand fans were almost the only ones to help people keep cool.

Chinese people started to use hand fans more than 2,000 years ago. The fans came in different shapes, such as round and square. They were also made from all kinds of materials. Palm （棕榈） leaf fans were cheap and easy to make. Feather fans （羽毛扇） showed the owner’s high status （地位）. Sandalwood （檀香） fans could send out sweet smell.

Later, hand fans became far more than just something that could cool you down. They developed into art works, in which Tuanshan （round fans） and Zheshan (folded fans) were the most common.

In the shape of a full moon, Tuanshan were usually made of silk.They had beautiful birds and flowers on them.Women especially those in the imperial palace （皇宫）, liked to use them. Meanwhile, men, especially the literati （文人）, used Zheshan.The literati liked them because Zheshan were usually made of paper and they could paint and write poems on them.It was a way for them to show off their ability in literature, painting and handwriting.Almost anything can be painted on Zheshan.

Today, Chinese people still use these fans.Next time when you are waving a fan, you may think of the stories behind it.

4 . When we play a game with our classmates or friends, we usually need to make some rules first. I think it’s very important to have rules.

There are lots of rules in my school. We have to get to school on time. We have to wear the school uniform on Mondays and Thursdays. We can’t run in the hallways. We can’t fight. I think it’s very good to have rules at school.

We have to follow traffic (交通) rules. We can go at green lights (灯) and have to stop at red lights. The traffic rules make us safe (安全的).

When we take a car or sit next to the driver, we have to wear the safety belts (安全带). Also, little children need to take the back seats. The car rules make us safe, too.

5 . The traditional Chinese lunar calendar(阴历) divides the year into 24 solar terms(节气). Lichun, the first of the 24 solar terms, lifts the curtain(窗帘) of spring. After that everything turns green and is filled with energy. People clearly see that the daytime is becoming longer and the weather is becoming warmer. Here are some things you might not know about Lichun.

As a solar term, Lichun entered people’s lives in the Spring and Autumn period. At that time, there were eight solar terms. According to some experts, the 24 solar terms were used for the first time in books during the Western Han Dynasty, when people set Lichun as the Spring Festival.

Wearing fabric swallows(织成的燕子) is a custom in some areas in Shaanxi. Every Lichun, people like to wear a swallow made of colorful silk on their chests(胸部). The swallow is a sign of spring and a symbol of success, wealth and happiness.

In China, it is said that the egg can be set upright on the first day of Lichun. It is believed that if someone can make the egg stand on the first day of Lichun, he will have good luck in the future.

In many parts of China, people follow the custom of “biting the spring” on the first day of Lichun. They eat spring pancakes, spring rolls(春卷) and so on.

7 . In England, people often talk about the weather because they can experience (经历) four seasons in one day. In the morning, the weather is warm just like in spring. An hour later, black clouds come, and then it rains hard. The weather gets a little cold. In the late afternoon, the sky will be sunny, the sun will begin to shine, and it will be summer at this time of a day.

In England, people can also have summer in winter, or have winter in summer. So in winter, they can swim sometimes, and in summer sometimes they should take warm clothes.

When you go to England, you will see that some English people usually take an umbrella or a raincoat with them in the sunny morning, but you should not laugh at them.

If you don’t take an umbrella or a raincoat, you will regret (后悔) later in the day.

8 . What would the world be like if cars could drive themselves? Imagine seeing an empty car passing by on its way to pick up its owner, or a car full of passengers who are reading, listening to music or even sleeping. But none of them are worried about the road ahead.

Well, all of this could be the future of driving. There are several companies, including Google, working on driverless cars. So far, no Google self-driven cars have gotten a traffic ticket (罚单), but some of them have been in accidents when other cars hit them.

These cars are now still in the testing stages (阶段). But, if the tests are successful, these electric self-driven cars could be put into use very soon.

The cars are so special that they can take the place of drivers during certain situations. They are able to park themselves, or slow down when they notice objects close by. They can also control the speed if there is danger.

Scientists and engineers believe, with the help of wireless signals (无线信号) , cameras and GPS, creating a safe self-driven car might be possible. The cause of deadly (致死的) road accidents is usually careless drivers or bad conditions. The self-driven car may be able to prevent these. However, some people don’t like the idea. American lawyer Whit Drake does not believe these cars are safe. He thinks that technologies can also be mistakes.

9 . Greeting people can be confusing (令人困惑的) during cross cultural (跨文化) communications.

Will a simple handshake do? Should you give a hug or offer a kiss on the cheek (脸颊)? People in different countries have their own greetings.

The COVID 19 (2019冠状病毒病) has challenged traditional greetings such as shaking hands, kissing and hugging. After all, close physical contact will increase the chance of spreading the virus (病毒). People have realized the risk and stopped using some traditional greetings.

Shaking hands is a common greeting. Now in the US, the elbow bump (碰肘) is the new handshake. US Surgeon General Jerome Adams introduced the elbow bump, which has been used by political (政治的) leaders, health officials and professional athletes (运动员). Brad Hazzard, a health minister in New South Wales, Australia, advised people to pat (拍) each other on the back in place of a handshake.

French Health Minister Olivier Veran has advised the public not to kiss on the cheek. Italian authorities (官方) have made the same suggestion. French lifestyle expert Philippe Lichtfus said simply looking into a person’s eyes is enough.

In the face of such changes, how should you go about changing the way you greet people? Australian etiquette expert (礼仪专家) Susan Wilson has suggested simply greeting people by looking them in the eye, smiling and saying hello.

Choose the best choice from A, B or C according to the passage.