Some people believe that colours can influence our moods. You may wonder whether it is true. In fact, colours can change our moods and make us feel happy or sad, energetic or sleepy. 【小题1】

●Calm colours

Have you ever walked into a room and felt relaxed? It could be because the walls were painted blue. Blue is a calm colour. It brings peace to our mind and body. Blue can also represent sadness, so you may say “I’m feeling blue” when you are feeling sad. 【小题2】 It is also the colour of purity. Many women like to wear white on their wedding day.

●Warm colours

Some colours, such as orange and yellow, can make you feel warm. People in cold areas prefer warm colours in their homes to create a warm and comfortable feeling. Orange represents joy. It can cheer you up when you are feeling sad. Yellow is the colour of the sun, so it can remind you of a warm sunny day. 【小题3】 Some people prefer this colour when they hope for success.

●Energetic colours

When you feel tired or weak, you should wear energetic colours like green. Green can give you energy, as it is the colour of nature and represents new life. 【小题4】

●Strong colours

If you require strength in either body or mind, red may be of some help to you. Red is the colour of heat. It represents power and strong feelings. 【小题5】 This may help when you are having difficulty making a decision.

Students attended (参加) a live (现场直播的) class given by the Shenzhou-13 members, Zhai Zhigang, Wang Yaping and Ye Guangfu, at the China Science and Technology Museum in Beijing, Dec. 9, 2021. It was a special course. It came from 400 km above the earth in China’s space station.

Wang first talked about their life and work in the space station. Wang said the water they drink is recycled (可循环的). There is no difference in taste between everyday and recycled water.

Next Zhai introduced the special clothes they were wearing in the space station. According to Zhai, it has many elastic bands (松紧带) inside to help them keep their bodies healthy.

Then Wang asked both the students on the ground and Ye to do the turn-around movement. The students were surprised to see that Ye could not do it. He finally made it with specific motions (特定动作), like moving a single arm in a circle.

At the end of the class, the three astronauts tried to answer students’ questions, like “Do stars still shine in space?”, “Do they have dreams while sleeping in space?”. Finally, the three astronauts ended up the class with their best wishes. The class was a big success and encouraged (鼓励) many students to study hard in order to get into the space one day.

What do you do when you want a cold drink? You probably get a drink from your icebox. But people did not have iceboxes before the early 1900s. How did they keep things cool before then?

In the past, it was difficult to keep food cold. Warm food spoils quickly. People tried many different methods to keep things cold. They used to put food in cool small rivers or in large holes under the ground near their homes. They also stored food like vegetables and fruits in rooms under their houses. These rooms stayed cooler in warm months. However, none of these methods was perfect.

What was a better way? Putting food on ice. In 1000 BCE, people in China collected ice and snow. Then they dug holes under their homes and filled them with the ice and snow. After that, they put their food in the holes. In many countries, people continued to do this for about 2, 000 years.

There are a few problems with this method. First, ice and snow are not to be found everywhere. Second, ice turns into water when heated. An American businessman named Frederick Tudor solved these problems. He wanted to carry ice to hot places, such as the Caribbean. In the early 1800s, he sent a ship full of ice from Boston, Massachusetts, to the island of Martinique. Almost all of the ice turned into water. After that happened, Tudor realized that he had to find a way to keep the ice at 0℃ or below. He spent ten years working on the problem. Finally, he tried putting sawdust-very small pieces of wood-between the pieces of ice. It worked! Sawdust keeps ice at 0℃ or below for a longer period of time.

People used to work hard to keep their food and drinks cold. Now, it’s much easier. The next time you want a cold drink, imagine your life without an icebox.