A smile will tell people around you that you are a kind and friendly person. However,many people don't smile because they think they ugly teeth. For example, one of my classmates, Mile, doesn't have very nice teeth,so thatis why he seldom opens his mouth.he even says that he has lost cofidence because of his teeth.So it is very important for us to look after our teeth. In fact, a lot of people have this problem. Some people inherit teeth problems from their parents,while others'teeth are damaged because of bad habits,like heavy smoking,eating too much sugar or not brush-ing teeth often.If your teeth are in bad shape, you should see a dentist and ask for help. They can help improve your teeth and tell you how to take care of then.
   Smiling can help you to feel more confident and make other people think of you as a more friendly person. If you want to keephealthy, you should not only smile but also laugh. An Indian doctor called Kataria said that young children should laugh about 300 times a day, wile adults should laugh between 7 and 15 times a day. So please take this chance to smile and laugh now!

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

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

      Though the PaperPhone 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 PaperPhone.

The scientists from Queen's University in Kingston, Canada said the PaperPhone 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 PaperPhone on May 10th this year.

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    Animals grow up in different ways. Some newborn animals are helpless but their mothers protect them. A newborn kangaroo is very small. It is only a few centimeters(cm) long. It closes its eyes and doesn't have hair. It stays safe in its mother' s pouch(育儿袋) for a long time.A newborn monkey can not walk. Its mother carries it everywhere.

Other baby animals can walk soon after they're born. They learn to run with their mothers when danger is near. A baby zebra can run, an hour after it is born.

    Some baby animals are born in a place that is safe. Baby wolves are usually born in big holes with little light. Other baby animals are born in the open. A baby elephant is often born on open land.

    Animals that drink their mothers' milk are called mammals. A mother bear's milk is rich. Baby bears have milk for a few months. This is the same with baby zebras. As baby animals grow, they need solid(固体) food. Baby lions eat what their mother can catch!

Life in 2060

    Let us suppose the life in A. D. 2060. It is fifty years later. Of course, things have changed and life is very different. Voyages to the moon are being made every day. It is as easy to take a holiday on the moon today as it was for the people in 1960 to take a holiday in Europe. At a number of scenic spots on the moon, many hotels have been built. The hotels are air- conditioned, naturally. In order that everyone can enjoy the beautiful scenery on the moon, every room has at least one picture window. Everything imaginable is provided for entertainment of the young and old. What are people eating now? People are still eating food. They haven't yet started to take on heir(继承) supply of energy directly like electrical current or nuclear power.

    But many foods now come in pill forms, and the food that goes into the pill continues to come mainly from green plants. Since there are several times as many people in the world today as there were a hundred years ago, most of our planet's surface has to be filled. The deserts irrigated with water and crops are no longer destroyed by pests. The harvest is always good. Farming, of course, is very highly developed. Very few people have to work on the farm. It is possible to run the farm by just pushing a few buttons now and then. Such would be our life in 2060.

    From a plane we can see the fields, cities, mountains or seas below. If we go into space, we see more and more of the Earth. People and man-made satellites have been sent out into space to observe the Earth carefully and people have learnt mire about the Earth in the last few years.

    The sea looks very beautiful when the Sun is shining on it. But it can be very terrible when there is a strong wind.

    The sea is very huge. It nearly covers three quarters of the Earth. The sea is also very deep in some places. There is one place where the sea is about 11 kilometers in depth. The highest mountain is the world is about 9 kilometers high. If that mountain was put into the sea at that place, there would be still 2 kilometers of water above it!

    In most parts of the sea, there are many kinds of fishes and plants. Some live near the top of the sea. Others live deep down. There are also a lot of small living things, and quantities of fishes live by eating them.

    The sea can be very cold. When people go down, the sea becomes colder and colder. Only some men could go down into the deep sea at first. But in 1970, five women scientists lived in the deep sea for fourteen days.

    We usually think that plants always stay quiet and never speak. Grass doesn't cry when you cut it; flowers don't shout when they're picked. But this view of the world couldn't be more wrong. Plants talk to each other all the time. Their language is one of chemicals.

    Over the years, scientists have found that different types of plants, from trees to tomatoes, send compounds(复合物)into the air to help neighboring plants. But exactly how plants receive and act on many of these signals is still a mystery.

    Scientists from Kyoto University in Japan looked at tomato plants that had been bitten by insects. To start out, they grew plants in two plastic bags connected by a tube(管子). One plant had been bitten by insects. The other was not bitten.

    They found that when insects bite plant leaves, the plants don't sit quietly. They send a chemical called "hexvic" into the air. Humans can't notice it, but these chemicals carry a smell that neighboring plants can notice. This way, neighboring plants realize the danger and begin to give off more "hexvic" to protect themselves.

    The same scientists continued their research by placing insects on the plants that had not been bitten. The plants were able to kill nearly 50 percent of the invaders, much more than their neighbor.

    It was surprising that the plants that had not been bitten didn't send the chemical until the received a warning message from their infested(受侵的)neighbor, the scientists said. These findings could be used to help farmers with the control of the insects which do harm to their plants.