The leaders （领导人） of 13 countries had a big meeting in St Petersburg, Russia from November 21 to 24, 2010.The meeting was about tigers. They talked about the ways to protect the animals in their countries. They agreed to spend more money protecting tigers and they wanted to double the number of tigers in the world before 2022.

    Tiger is one of the world's most endangered animals. The World Wildlife Fund （WWF） says, there are only about 100,000 wild tigers now. And the number is becoming smaller and smaller. 'If nothing happens, tigers will face disasters,' said WWF spokeswoman Marie von Zeipel.

Nine types of tigers lived 100 years ago, but now at least three of them have died out. ‘If people leave tigers alone and don't kill them, then the number of tigers will double in 10 years,' said Jean-Christoph Vie, a French tiger expert (专家).

    China is one of the 13 countries where tigers live. There are about 50 wild tigers in China now. They are the Bengal tigers in Tibet, Indochinese tigers in China's southwest, and Siberian tigers in the northeast. The South China tigers lived in southeast China many years ago but disappeared in the 1970s. Many experts think they have already died out.

    Do you notice music playing there when you go somewhere? Today most stores, stations restaurants and other places play music. You might even hear music in an office or on a farm.

Scientists believe that music changes the way people behave. They think that Western classical music makes people feel rich. When a restaurant plays classical music, people spend more money on food and drinks. When the restaurant plays modern music, people spend less money. Without music, people spend even less.

Scientists also believe that loud, fast music makes people eat faster. In fact, people eat their food faster when the music gets faster. Some restaurants play fast music during their busy hours. This gets people to eat faster and leave more quickly. Restaurants can make more money this way.

Some scientists think that music makes people think and learn better. They say that music helps students be more active. It is true that people learn better when they are relaxed. And listening to music can help people relax.

    Next time you hear music somewhere, be careful. It might change the way you do things.

    In most parts of the world, many students help their school make less pollution. They join “environment clubs”. In an environment club, people work together to make our environment clean.

     Here are the things students often do.

      No-garbage lunches! How much do you throw away after lunch? Environment clubs ask students to bring their lunches in bags that can be used again. Every week they will choose the class that makes the least garbage and report it to the whole school!

    No-car day! On a no-car day, nobody comes to school in a car, not only the students but the teachers as well! Cars give pollution to our air, so remember to do such things: walk, jump, bike or run! Use your legs! It's very fun.

    Turn off the water! Do you know that some toilets can waste twenty to forty tons of water an hour? In a year, that would fill a small river! In environment clubs, students mend those broken toilets.

    We love our environment. Let's work together to make it clean!

    This is the end of our radio programme. Wish you have a good night. This is Grace Brown.

    Some animals sleep during the wintertime because the weather can be very cold and it is difficult for them to find food. They can sleep for a long time. This kind of winter sleep is called “hibernation”.

    If an animal moves about a lot, it needs food. Hibernating animals do not need to eat much because they are not moving about. Their hearts(心脏) beat very slowly and they also breathe(呼吸) slowly. They find a place that is sheltered(遮蔽的) from bad weather and where they are out of danger. Their body fat(脂肪) keeps them alive and warm.

    Some animals, such as bears, may wake up from their hibernation on warm winter days and then quickly go back to sleep again when they see the snow is still thick on the ground. When the weather becomes warmer in spring, the animals start to wake up and look for food.

    Mobile phones are very popular with people. They are becoming smaller and more convenient.

    Now the scientists in Canada made a smart phone (智能手机)from electronic paper. The Paper Phone is flexible. People can control it by bending it or writing on it with a pen.

    Though the Paper Phone is only millimeters (毫米)thick, people can do many things with it. For example, people can use it to make phone calls, read books, watch movies and play music. So many people use it as a computer.

    The scientists think there will be no paper in the office. And people can store what they want in the Paper Phone.

    The scientists from Queen's University in Kingston, Canada said the Paper Phone would be in style in the future. It may be the end of paper and printers.

    To make people be interested in this kind of mobile phones, the scientists will make it more beautiful. People will see the Paper Phone on May 10 this year.

    Every day there is less and less space on Earth for rubbish. Yet every day we make more and more rubbish. What can we do? We can recycle some of our rubbish. Recycling means that the rubbish will be made into something that can be used again.

    Recycling helps Earth. And it saves space in rubbish dumps. Half of everything that we put into landfills could be recycled instead. In fact, most things made of paper, metal, glass and plastic can be recycled.

    Paper can be broken into small pieces and made into new paper. Steel and aluminum cans(金属雄)can be melted down(熔化)and made into new cans. The same is true of glass bottles. This can be done over and over again. Recycling doesn't take as much energy as making these things the first time. So we can use less of Earth's fuel resources.

    Plastic can be melted down, too. Then it can be formed into park benches, playgrounds and so on. Some people call plastic the "wood" of the future. Things made of plastic will last about 400 years-even if they stay outside in the weather. No wood can do that!