According to a new survey, students' safety has become a big problem. Nearly 50% of students say they are worried about robbery on the way to and from school. Now in main big cities in China, some schools have taught an unusual lesson: self-protection. Students like this lesson because there are no exams or boring classes. And they can learn how to save lives and know how to stop danger before it really happens.

      Chen Haoyu, a teacher at Beijing No. 25 Middle School, gives young students advice on how to deal with danger.

★If you are robbed

     Keep calm. lf you can not cry for help or run away. Give the robber your money. Try to remember what the robber looks like and tell the police later.

★If you are in a traffic accident

     If a car hits you. You should remember the car number. If it is a bicycle, try to call your parents before you let the rider go. This is because you don't know how seriously you are hurt

★If it is raining hard and there is lighting

    Don't stay in high places and stay away from trees.

★When there is a fire

    Get away as fast as yon can. Put wet things on your body and try to find an exit. Do not take the lift.

★If someone is drowning

     If you can't swim, don't get into the water. Cry out for help.

      Remember that danger is never as far away as you think. Take care of yourself at all time!

      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 car has gotten a traffic ticket, but some of them have been in accidents when other cars hit them.

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

      The cars already have many features（特点）allowing them to take the place of drivers during certain situations. Some features include cars being able to park themselves, or slow down when they notice objects close by. They can also control the speed if there are dangerous conditions.

      Scientists and engineers believe, with the help of wireless signals, cameras and GPS, we are now at a stage where creating a safe self-driven car might be possible.

      The cause of deadly road accidents is usually careless drivers or dangerous conditions. The self-driven car may be able to prevent these. However, some people do not like the idea. American lawyer Whit Drake, for example, doesn't believe these cars are safe. He thinks that technologies can also be mistakes.

Researchers have discovered the first Earth-sized planet. It was first marked by NASA's Kepler telescope(望远镜) so it's called Kepler-186f. It lies about 500 light years from Earth and goes around its star. The planet is the right distance from its star for water: not too close or not too far. Water is one important condition that scientists guess is necessary for life. So it could have water and possible life. It's called a true Earth cousin.

"This planet is an Earth cousin, not an Earth twin," said Barclay, who is among a team of scientists reporting on the discovery in the magazine Science this week.

"It's very exciting to find a planet similar to the Earth," Barclay said, "It's not easy work because things change as we get more measurements."

Scientists don't know anything about the air of Kepler-186f, but it will be a task for future telescopes which can study for chemicals that have something to do with life.

    "It's possible for life to live in this planet, but that doesn't mean there is life in it," Barclay said.

So far, scientists have found nearly 1,800 planets in the universe.

"The past year has seen a lot of progress in the search for Earth-like planets. Kepler-186f is very important because it is the first planet that is the same temperature and is almost the same size as Earth," scientist David Charbonneau wrote in an email.

    In ancient Chinese stories, the moon is home to Chang'e and her pet rabbit Yutu. Now, Chang'e and Yutu are really there!

    On Dec. 2, 2013, the Chang'e-3 lunar probe（月球探测器）took off from Sichuan, China. On Dec. 14, 2013, it landed successfully on the moon. Several hours later, Yutu, China's first moon rover（月球车）, "walked" out of the probe and onto the moon.

    Yutu is a big robot that weighs 140 kg. It is about 1.5 meters long and 1.1 meters tall. It has six wheels and travels at 200 meters per hour.

    There are cameras on both Yutu and Chang'e-3. They can take pictures of each other. That's how Yutu got is first picture on the moon.

    Yutu and Chang'e-3 will explore（探索）the moon.

    Yutu can walk around and work for three months. It can look for natural resources（资源）on the moon. Chang'e-3 can work at the landing site for one year and it can watch the space from the moon.

    They both get energy from the sun. So they "get up" to work when the sun rises, and "go to sleep" at night.

    China is now the third country in the world to soft-land on the moon after the US and the former Soviet Union.

    Also, China is planning to send its Chang'e-5 lunar probe around 2017. The probe will fly back to the Earth and bring natural resources from the moon.

    When will China fly a human to the moon? There's no plan yet. But the door is now open.

    Artificial intelligence(AI)(人工智能)is the ability of a computer program or a machine. The computer or the machine with AI can think and learn. It is also a field of study that tries to make computers "smart". John McCarthy, a scientist, came up with(提出)the name "artificial intelligence" over 60 years ago. Many things such as learning and problem solving can be done by computers, though not in the same way as people do.

    An unusual goal of AI research is to create computer programs. They can learn, solve problems, and think logically(逻辑地). At present, Al can successfully understanding human speech, recognizie (识别)human faces, operate self-driving cars and compete in some game systems like playing Chess. However, Some people also consider(认为）AI a danger to humans if it develops too quickly. A famous British scientist also was not for this kind of technology.

    Math is the basic language of AI. If students are good at math, they will be more likely to become successful AI designers(设计者)in the future. We need not only bright students, but also average(普通的)students. As for(对于)average students ，if they get enough math skills, they can also become successful AI designers. Besides, a good knowledge of computer science is also necessary for AI designing.

    Scientists hope to create creative(有创造力)and emotional (有感情的)AI. The AI can possibly understand human feelings or create art. Many ways and tools have been tried to discover this wide and exciting field.