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    Plants are very important. This is because plants can make food from air, water and sunlight. Animals and man cannot make food from air, water and sunlight. Animals can get their food by eating plants and other animals. Man gets his food by eating plants and animals, too. So animals and man need plants in order to live. This is why there are so many plants around us.

    There are two kinds of plants: flowering plants and non-flowering plants. Almost all the trees around us are flowering plants. You can know some trees from their flowers and fruit. Non-flowering plants do not grow flowers. You cannot see many non-flowering plants around you.

    If you look carefully at the plants around you, you will find that there are many kinds of plants. Some plants are large and some are small. Most of them are green. Thanks to the plants around us we can live on earth.

    How much do you know about the bird world?

    Birds use three gaits: walking, running and hopping．

    In walking, the left and the right feet move in turn (轮流)．Each foot is on the ground for more than half the time, so there are more times when both feet are on the ground．In running, each foot is on the ground for less than half the time, and there are more times when both feet are off the ground．In hopping, the feet move almost at the same time．This means that for much of the time both feet are off the ground．

    Middle-sized and large birds walk at low speed and either run or hop at higher speed．Small birds, such as sparrows and swallows, usually do not walk, because walking may be too slow for them．It seems that the more time a bird spends in trees, the more likely it is to hop．Perhaps there is wide space in a tree between one thin branch (树枝) and the next, so walking is not a good choice, while on each small branch there is enough room to set both feet down side by side, so hopping seems to make sense．

    Animals United is a 3D German cartoon which is directed by Reinhard Klooss and Holger Tappe. It is a story about animals that get together to find water. Along their journey, lots of funny things happen, and of course, they have a lot of adventures.

    The animals in the grasslands in Africa are waiting for the coming flood. However, this year's flood seems to come later than in other years. The animals become upset and worried. At the same time, some animals from other places come to the grasslands to look for peace. However, the situation seems worse because the water is becoming less and less. So they decide to look for the river.

    Finally, they find the reason why they don't have any water to drink. A dam(坝) has been set up so that humans can have a better life. After a long fight with humans, they let the world know that animals are in danger.

    This film is about environmental matters. The humans are the bad and the animals are the good. This film is to give humans a warning that they must not destroy the homes of animals or damage nature in order to improve their own life. Humans should know that animals also have their own world.

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    Some of the greatest problems we face today are the destruction (破坏) of our environment. Brown clouds, polluted water, endangered wild animals.., these problems seem so huge.

    So my family does what we can. We take cloth bags to stores instead of using plastic bags. We walk where we don't have to drive...

    But does it do any good? When I am the only one in line at the market with cloth bags, am I doing any good? Does my walking to stores make any real difference to the world?

    I recently learned something about flamingos (火烈鸟) which like to get together in groups of a thousand or more. Every year, when the time comes for migration (迁徙), a few of them first takeoff from the lake. But none of the others seem to notice, so the small group returns. However, the next day they try again. This time few more fly along with them, but most of them still pay no attention, so they return again. They try for several times. Every time a few more birds join in but, since the thousands of others still take no notice, the great migration plan is once more stopped.

    Then one day something changes. The same small group of birds once again starts flying and a small number more join in just as before, then more. Finally, they all take flight and the migration really begins. What a spectacular sight it must be—thousands of flamingos taking off into the sky at once!

    A few can make a difference. Even if you're the one to take the first step, and continue trying, others will someday take notice and together we will solve even our greatest problems.

    Stop reading for a minute and think about what you see when you look up at the sky on a clear night. You probably see many stars(星星). Long long ago, farmers watch some stars to know when to plant their crops. Travellers did so to find their way in the dark. Today stars are still important to some people.

    Scientists find that most stars are very big. In fact some stars are so far away that it would take millions of years to get to them even by spaceship.

    Another thing we know today about stars is that some are made up of(由……组成) hot gases. The gases are so hot that they send out light. If you watch a star carefully, you may notice that it twinkles(闪烁) sometimes. As you may understand, light from a star must shine through the air before you can see the star. Air is always moving, it makes light from the star move back and forth. When the light moves, it makes the star twinkle. Stars also have different colours. The colours of a star depend on how hot it is. To our surprise, the cool stars are red and the hottest stars are white.

    More than 1,000 different kinds of pieces of plastic, including 115 cups, 25 bags, four bottles and two pairs of shoes, have been found inside a dead whale(鲸鱼) in Indonesia, according to local officials.

    When the whale was found on the island, it was already decomposing when animal doctors arrived. So they were unable to be sure if the plastic caused its death, said Lukas, the leader of the World Wildlife Fund in Indonesia. The plastic weighed about 6 kilograms, or 13 pounds, he said.

    But pictures of the dead whale caused a warm discussion. The people in the country have started to realize that it is because of using too much plastic. So has the government. Indonesia, a nation of about 260 million people was the world's second-biggest producer of plastic waste in 2018, behind only China.

    If the whales eat too much plastic, they will have a wrong feeling. They think that they are full. And that will lead them to eat less food that provides all the good things they need, said Nicholas who is the leader of the Ocean Conservancy. Moreover, eating too much plastic can make them reduce their weight, their energy and slow down their swimming. As a result, whales are easier to be hurt by the sharks and many other dangerous animals in the sea.

    More than 800 kinds of animals in the sea are affected by about 8.8 million tons of plastic which is thrown away freely in the ocean each year. Plastic can also stop the animals moving freely and sometimes they will cause them to die because they have to be under the water for too long. Some plastic can make a small hole in their stomachs after they eat it.