Although cats may be one of the most popular pets today, little is known about how and when humans and cats set up their close relationship.

    The earliest evidence for human–cat interaction dates back to prehistoric Cyprus(史前塞浦路斯), where the remains of a wild cat and a human — dated 9,500 years old — were found buried together

A new study in the Proceedings of the National Academy of Sciences has confirmed the first direct evidence of a human–domestic cat relationship among Chinese farmers 5,300 years ago. Researchers studied the bones of cats, dogs, deer and other animals unearthed in an excavation (挖掘) near a village in Central China. By using some ways, scientists showed that the cats were living on a mostly millet(黍)–based diet, just like the domesticated dogs and pigs from the site.

"The most reasonable explanation for a high consumption of millet–based food is that the cats had formed a stable and mutual relationship with humans and could easily feed on rodents (啮齿动物) around human villages, find leftover food or even have been fed by people intentionally," said Hu Yaowu from the Chinese Academy of Sciences in Beijing, whose research focuses on the relationship between humans and domesticated animals.

    "It is very interesting for us to find the consumption of millet-based foods by the cats, since this kind of evidence had long been missing.” Hu explains. Since cats usually eat meat, such a diet would be unexpected, unless the cats were being fed by people, the study argues. The researchers also found that one of the cats survived to reach old age, implying that it had a safe place to live and enough to eat.

Why the farmers wanted to keep cats nearby or make them "pets" could be answered by other evidence. Chinese archaeologists found some storage containers were specifically designed to keep out rodents — a vermin (害兽) that cats could certainly have helped with.

The simplified theory is that rats were attracted to the food of farmers, and so were harmful to farmers. Cats were attracted to the rats, and so farmers formed a mutually beneficial relationship with cats, taking care of them in return for pest control.

    Millions of children in the United States go to summer camps. Some go to play outdoors at traditional camps in the woods, in the mountains or on lakes. But families now have many choices of special camps. These can be in the middle of nature or a big city. Special camps offer young people the chance to learn about different subjects: Anything from space exploration to business to medicine.

    In technology camps, one subject that children can learn about is video game design. They learn how to use computer programmes to create games of their own. One programme that teaches video game design is called Cybercamps. Children can learn how to design their own virtual(实际上的) worlds to set their video game in. Then, they programme their own rules and objects into the game.

    Cybercamps also offers courses in robot building and Web design. A recent story in the Washington Post described how one child made a robot that could sing a song. Another made a robot that could follow a black line drawn on a piece of cardboard. Also, children can learn how to make Web sites. One child made a site for pokeman, one of his favourite cartoon shows.

    Scientists have been experimenting with four-leg robots for years. They want to use robots to carry heavy things over difficult land.

    But providing enough power for those kinds of robots has been a problem. Now, that has changed. Engineers at MIT have designed a running robot that runs on batteries. Scientists say their robots will soon be able to run like cheetahs, the fastest land animals on Earth.

    One difficulty in designing these types of robots continues to be providing power. These machines are still quite heavy and they need a lot of power to run. But the cheetah-like robot designed by engineers at MIT is light enough m run on batteries. The robot weighs just 30 kilograms. The robot needs only about 700 watts of power to run. This robot can actually jump 40cm high and it can land very safely and then it can run. The robots limbs and other parts were made in a three-dimensional or 3D printer. A strong, light-weight material called Kevlar is used to make the robot's part stronger.

    But the development of MITs robot is not without its own set of problems. The robot's limbs must support heavy force, and sometimes they break.

    Scientists say the new technologies used on this robot may be used in the making of limbs for disabled persons and other machines. Some of those machines may help save humans from performing difficult and dangerous jobs.

    Do you know pigeons(鸽子)? They are kind of birds. They are in white and grey. Some people say they are not beautiful but they are cute and smart. Many people keep them as pets. Why do people say pigeons are clever? Because pigeons can take letters from one place to another. And they know the way home. We often see the picture of a pigeon with an olive branch(橄榄枝)in its mouth. We call them peace pigeons. They are the symbol of peace.

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    Earlier this year, China achieved a new milestone(里程碑) in space exploration(探索). On Jan 3, Chang'e 4 became the first space probe(探测器) in history to land on the far side of the moon, People's Daily reported.
    From Earth, we can only see one side of the moon. The other side has been a mystery. Scientists have long wondered what lies on this side of the moon.

    Chang'e 4 has sent back photos of the far side of the moon. It is also used to carry out experiments, such as growing seeds in a low-gravity(低重力) environment. The data(数据) collected from these experiments could be used to help us build a base on the moon in the future.

    The success of the Chang'e 4 mission(任务) is a main achievement for China's space program. It marks a new stage in China's deep space exploration, said Wu Yanhua, head of China National Space Administration.

    China launched(启动) its lunar(月球的) exploration program in 2004, naming it Chang'e. Chinese scientists set three goals —“orbiting(环绕运行), landing and sample(样本) returning”— referring to launching probes that could circle around the moon, touch down on its surface and bring lunar materials back to Earth.

    Chang'e 4 has realized the goal of landing. The third will be achieved during the Chang'e 5 mission, which is set to take place before the end of this year, China Daily reported.

    Following the success of the Chang'e missions, Chinese scientists are looking even farther into our solar system (太阳系). China's first Mars(火星) mission is expected to be carried out by 2020, Wu said.

    When you carry your heavy schoolbag on the way to school or home, do you know the fact that the heavy schoolbag influences your interest in learning knowledge? Don't worry. You may be able to say goodbye to your heavy schoolbag in the near future.

    Instead of burying(埋葬) your face in an ocean of textbooks, newspapers, magazines and novels, you will soon find that an E-book reader can take the place of them all.

    An E-book reader is a new kind of mini machine designed to hold thousands of text files and display them on the screen as real text printed(印刷) on a paper page.

    In the same way in which the iPod(a kind of MP3) has changed the way people enjoy music, E-book readers could change the way that books are read. Some scientists have predicted that E-books will be used widely in our daily life, especially in schools.

    The size of an E-book reader is the same as that of real books. Its screen is different from that of a computer. It is as thin as a piece of paper. The words on an E-book reader's screen look exactly the same as those on real pages. However, you can do more with an E-book reader than you can with a real book. The reader can change the size of the words and connect to the Internet to download new books.