Nobody knows how many different languages there are in the world. The most widely used language is English. It's used by business people, airline pilots all over the world. It's also the first language of sports and science. So it's very important for us to learn English.

    English is most widely spoken in the world, while Chinese has the largest number of speakers. There are not only over one billion people living in China, but also many Chinese people living outside China. You can find large or small groups of Chinese people living in almost every country in the world.

    There are some other important languages in the world, too. Chinese is of course very important, especially in Asia. Arabic is widely spoken in many parts of Asia and Africa. Russian is spoken both in Europe and Asia. French is widely understood, not only in Europe, but also in parts of Canada, Africa and Asia. Spanish has a growing number of speakers all over the world, especially in Central and South Africa.

    What language do people speak in the United Nations? There are so many different languages in the world, but they decide to use only six of them. They are Arabic, Chinese, English, French, Russian, and Spanish. Everything spoken or written in one language is translated into the other five.

    There are many wetlands in China and some of them have become the world's important wetlands. The Chinese Yellow Sea Wetlands are among them. They are in Yancheng, Jiangsu Province. They are home to many different kinds of animals. The world's largest Milu Deer Nature Reserve is in them. More than 700 Milu deer live freely there. There are not many red- crowned cranes in the world, but every winter you can see some in the Red-crowned Crane Nature Reserve in the Yellow Sea Wetlands.

    The temperature in the wetlands is usually neither too high nor too low. There is a lot of rain and sunshine too. They are really good places for wildlife. Offering(提供) food and home to some special kinds of animals is not the only reason why we need to protect wetlands. Wetlands are important because they also prevent flood. But some people want to change the wetlands to make more space for farms and less space for wildlife.

    Luckily, more and more people are beginning to realize the importance of wetlands and wildlife. Every year, on February 2nd, many activities are held to tell people more about wetlands.

    What does it mean to be green? "Green" is more than just a color. It also means taking special steps to protect the environment — the water, the land, and the air we breathe. Why green? Plants are green, and without them the earth wouldn't be such a lovely home for us human beings.

    Sometimes people call our society a "throwaway society". That means we are always throwing away old things and buying new ones. Many times, if you no longer need something, someone else just might need it. For example, if your brother is old enough not to play with his plastic bike, why not give it to another family who has a little kid so that they don't need to buy one? And one less large plastic toy doesn't need to be produced.

    Recycling （回收利用）has never been easier. Many organizations will pick it up right in front of your house and some towns even require （要求）it. Tell your mom or dad you want to become "Chief of Recycling" for your family. Now that you know what things you can recycle, find a place to keep them. Make sure you encourage everyone in your house to think whether things can be reused or recycled before they're thrown away.

    Almost everyone likes traveling. But next time before you travel around the world, take a look at your own backyard. Is there a place where you could plant a tree or put in a little fruit or vegetable garden? If so, get there and get your hands dirty. Then you can watch with pride as your tree takes root, and your garden plants grow into big plants full of ripe, red tomatoes or tiny, juicy blueberries. Who knew being green would taste so good?

Have you seen any scarecrows (稻草人)? In the countryside of our country, some villagers like to set up some scarecrows in the fields in order to prevent birds from harming their crops. They think that this can play a role in driving away birds. In fact, not only farmers love to use scarecrows, but also some airports have installed scarecrows in such a developed technology today, which plays a very good role in driving away birds. Some people will say that birds are not fools, and they will come back to eat after a long time. So do the birds really feel scared? Can scarecrows really play a role in driving away birds? Not very — unless you're willing to put some extra(额外)effort into them.

While traditional scarecrows who couldn't move do work against "pest birds" (eg. crows and blackbirds), the effect is almost always temporary (暂时的). Over time, the birds get used to scarecrows who couldn't move and reuse their destructive (破坏性的)habits.

However, a few tricks can up your scarecrow's game. Researchers have learned that those with realistic facial features(特征)and brightly colored clothes are better at driving away birds. Also, moving a scarecrow around every few days often helps. According to several studies, flailing(大幅波动) scarecrows get the very best results.