Have you ever rubbed your hands together when they get cold? Why do we do that? We do that for friction. Friction happens when two things that aren't very smooth rub together to make heat energy. The faster you rub two things together, the more friction (and heat) you can make. Let's discover friction!

      The Milu deer is a kind of animal with large horns(角). They were very common in China long ago. They lived together and ate grass and the soft parts of trees. In the past, people did not protect the Milu deer and killed them for food or sport, so they disappeared(消失) from China .

      Luckily before all of them disappeared, the Duke of Bedford(贝德福特公爵) took some to Britain. The Milu deer like the cool, wet weather in England and their numbers increased(增长) year by year. As a result, when in1985, the government of China wanted to bring back the Milu deer, the Duck of Bedford was able to help. The first deer came back to China to the Nanhaizi Milu park near Beijing and to Dafeng, Jiangsu Province.

      Since they returned to China, their number has grown quickly .There are now so many of them that a new park has been opened for them in Hubei Province. Now the Milu deer live in the wildlife parks and have good protection. We hope that one day they can live in the wild again.

    Terrafugia Company has said that its flying car, named Transition, has successfully finished a 37- second test flight.

    On March 5th, 2009, at Plattsburgh International Airport in New York. The company's chief pilot, Phil Meteer, piloted the flying car.

    Transition is a two-seat airplane that can take off and land at airports as well as drive on roads.

    The company said that the flying car can travel at speeds up to 115 mph in the air, drive at highway speeds on the ground, and fold up (折叠）to fit in a garage (车库) 81 inches wide and 80 inches high.

Hospitals could use it to transport patients so as to avoid road traffic. It may start running on wheels, and when it gets to traffic lights it can fly overhead the lights and keep its way forward. So it's good news to avoid traffic problems and the traffic accidents.

But some people say this is a going airplane rather than a flying car, at least on the appearance. Anyway, we are happy for scientific-technical progress, what a fantastical world in the near future!

    Today there are 6 billion people on the earth. By the year 2050 there may be 12.5 billion. There are a lot of people to feed. We need more food.

One way to produce more food is by growing stronger plants. For thousands of years，farmers have made plants better. Every season, they pick the best plants for the next season. It works very slowly. Since 1983, scientists have been able to change plants more quickly by changing their genetic material (遗传物质). Foods from plants grown in this way are called genetically modified foods (转基因食品), or GM foods.

    By changing the genetic material of a plant, it is possible to make new plants. They make plants which are strong against plant diseases. They can also help with our diseases: a kind of rice is being prepared, for example, which stops people from becoming blind.

    Rich countries produce GM foods because they are easy to grow and bring in more money. Poor countries are interested in them because they help produce more food.

    GM plants are not natural. No one knows how good or bad they are. Making GM foods is only one way of feeding people in 2050. There are strong feelings against them, because they are unnatural. They may feed people, and then hurt them or their children later. But, both rich and poor countries are very interested in their use, and they are not going to go away. In 2050, we may think differently about them.

    Do you want to know what our life will be like in the future? Let's have a look. You may get a surprise.

    You will go to the kitchen when you are hungry. You will give orders to the kitchen robot. The robot will find a special food for you in a few minutes. Then it will bring it to you.

    In the kitchen you will find a special food machine. The food machine will tell you what your body needs. It will help you eat healthily. The food machine will be connected with (连接) the kitchen robot. The robot can get messages from the food machine.

    After having a meal, you can go to your home office. You will work at home and you don't need to go out to work anymore. You will have a special information screen. When you receive a message from a friend in America, your information screen will be turned on automatically(自动地). Your friend's face appears on the screen. Then you can talk to your friend easily.