People already know a lot about animals. However, there are still some things about animals that may surprise you. Here are some facts about animals you probably didn't know.

    Cows do have best friends and feel stressed when they are separated. Scientists have found that cows are very social animals and a cow always makes friends with other cows. When a cow is with its friends, it feels relaxed, compared with when it is alone.

    During breeding season, a male penguin (企鹅) will offer a small stone to a female penguin as a gift. If she takes it, they will become partners. When the female penguin lays an egg, she and her partner may carry it on their feet, because some penguins don't build nests (鸟巢).

    Crocodiles (鳄鱼) swallow (吞) stones. Crocodiles always swallow their food instead of eating it like other animals. They swallow stones which break the food into very small pieces in their stomachs. These stones may stay in their stomachs all their lives.

    Elephants use plants to treat pain or other illness. Scientists once found a pregnant (怀孕的) elephant in Africa who ate a kind of plant which was not part of her normal food. Four days later, she gave birth to a baby elephant. The same plant was used by the local pregnant women.

根据短文内容,判断下列句子正误。

    Honey to treat a wound. Eat cherries(樱桃) if someone has a pain in his knee. Your grandmother is probably satisfied with her old-time treatments and now science is catching up with them. Researchers have produced hundreds of studies in the past five years about these grandmothers' old-time home treatments. They are often natural, different from the medicine from the hospitals. Here are some old-time treatments which have been proved（证明） to be useful by the scientists.

What do you know about folk or traditional art in China? Each different part of China has {#blank#}1{#/blank#} (它的) own special forms of traditional art.

Chinese paper cutting, or jianzhi, is a kind of folk art. People who can make paper cutting take {#blank#}2{#/blank#} (骄傲) in it. It's a way to show people's hope and feelings. Paper cutting sounds very easy but it can be difficult. Red paper usually {#blank#}3{#/blank#} (与……联系) with happiness in Chinese culture. The most common pictures are flowers, {#blank#}4{#/blank#} (动物), xi(喜) and fu (福). They are put on windows, doors and walls {#blank#}5{#/blank#} (作为) symbols of wishes for good luck.

Chinese clay art is {#blank#}6{#/blank#} (广泛) known and popular all over the country. Now many kids learn to make it in schools or even in {#blank#}7{#/blank#} (公开的) places. To make Chinese clay art, the Chinese shape the clay by hand into things, such as cute children or {#blank#}8{#/blank#} (生气勃勃的) characters from a Chinese fairy tale or historical story. After the things get dry in the air, they are fired at a very high {#blank#}9{#/blank#} (热，高温) and then polished and painted. It takes several weeks to {#blank#}10{#/blank#} (完成) everything. Although they look so small, they look very real. These small pieces of clay art show the love that all Chinese people have for life and beauty.

A strange way to get relaxed has become popular to cities across China. That is hugging trees. Young people feel comfortable after tree- hugging.

Hundreds of people online share their tree- hugging experiences. They think they feel less stressed (有压力的) and worried. It is also a way of keeping a close relationship with the natural world. By hugging a tree, some of them feel the tree is hugging them back.

Jenny gave up her job because of too much work stress. According to her, hugging trees helps her a lot . She enjoys herself in hugging trees." Hugging trees helps me relax and lets me go back to a natural state(状态). I feel so free and feel the world is so big."

In fact, hugging trees is a kind of psychological therapy (心理治疗). It first came from northern Europe. In northern Finland, there's even a tree- hugging competition every August. A study shows that hugging can lead people to give off hormone(荷尔蒙). Hormone can give people feelings of love and make people less stressed.

Though tree- hugging is helpful for people's body and mind, there are many things we should think about before we do that.

Secret of the best stone

Do you love skipping stones (打水漂) across the water? Then, you should know the best skipping stone is flat, but no heavier than a tennis ball, is also good. 

That's because…

When a heavier stone hits the water, a bigger part of it goes under the water so it gets a stronger push from the water. 

*Top tips:

1. Find the right stone. 

2. Flat, calm water is best, like a lake or pool. 

3. Turn the stone around quickly when you throw it. Don't throw hard. Instead, try to throw the stone quickly. 

4. The best angle (角度) to skip the stone is 20 degrees. （Picture 1）

*The best way to hold a stone:

Hold the stone between your thumb and middle finger. Put your index finger around the edge of the stone. (Picture 2)

*The biggest number of skips of a stone on the water is 88. (Picture 3)

 Picture 1                Picture 2              Picture 3

Touching China is a TV program on CCTV played once a year. It first appeared in 2003. Tenrole models were praised in the program for their moving stories and great achievements for our society. 

Wu Yuren, a 74-year-old physics teacher from Tongji University in China, was among them. She won the award for her efforts to share knowledge through short videos. By the end of 2023, Wu's popular physics experiment videos had caught over 5. 2 million fans' attention. 

In her short videos, she often wears a coat with several pockets and takes magical "toys". She uses them as teaching tools. She is able to make use of these everyday objects to explain physical questions in a simple way. 

"I made these videos to make young people curious about common life. And I hope they can use everyday tools to experience the fun of discovering the truth of science, "Wu said. 

Wu has been spreading physics knowledge actively for 16 years. She said children's interest in doing experiments made her keep making videos. To guide students to put interest into experimental research, Wu is going to put up online courses as well as short videos. 

According to CCTV, her videos are like "classrooms without walls". The words of the Touching China Award said, "The popularity created by gray-haired people has created real energy. "