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    The koala is unique (独特的) to Australia and is an important symbol of the country. The koala is found in open eucalypt (桉树) forests in south-east Queensland. Even if it is called koala bear, this animal has nothing to do with the actual bear. Koalas have thick fur and large cars.

    Their broad, flat nose makes them look cute, similar to teddy bears. In fact koalas aren't cute. They have sharp teeth and very sharp claws (爪)! Koalas are marsupials (有袋类). This means the mother carries her baby in a pocket while it develops, similar to a kangaroo. The baby koala lives in its mother's pocket for the first six months of its life.

    The name “koala” comes from a native Australian word that means “no drink”. The koalas get almost all their water from the eucalyptus leaves they eat. That's where they get their food too.

    Koalas eat only eucalyptus leaves. The eucalyptus trees are where the koalas live, it's also where they sleep. Koalas sleep about nineteen hours a day!

    Why do they sleep so much? Some people think it's because they're lazy. But koalas aren't lazy. They sleep so much because there isn't much nutrition (营养) in eucalyptus leaves. Koalas store hardly any fat, so they must save their energy. One way to do this is to move slowly and sleep a lot. After a day of sleeping they like to move around and eat just after sunset. They live alone most of the time. Koalas are very protective of their trees. If a koala sees another koala eating in its favorite tree, it might tell the other koala to leave by “barking” at it. Koalas do “talk” to each other.

    Besides barks, the males make a deep grunting (呼噜的) sound.

    The mothers and babies talk in soft clicking sounds. If they get scared they may scream like a baby. The koala is also an excellent swimmer.

    They are able to cross rivers to escape from heavy flooding (泛滥).

    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.

    It is a question that has confused parents for many years: why do children refuse to eat greens?

    Now, two American experts believe they have the answer.

    After studying dozens of babies as they played with various objects, the researchers noted that they were far more unwilling to touch plants than other things. They believe this is because evolution (生物进化) has biologically made children be wary of plants.

    Due to susceptibility (敏感性) to illness or injury in the early years of life, the body has designed an inner defence mechanism (内部保护机制) that limits a child' s contact with plants, they think. The researchers believe this is why children turn their noses up when faced with a plate of broad beans.

    The findings are published in a paper by Dr Annie E Wertz and Dr Karen Wynn, both psychologists at Yale University.

    They wrote, "Throughout human evolution... plants have been important in human's life. Yet, for all of these benefits, plants have always caused very real dangers."

    "Plants produce toxins (毒素) as defences that can be harmful, or even deadly. Some plants also produce physical defences, such as thorns（荆棘）can damage tissues (组织) and cause effects over the whole body."

    They added, "We predicted that babies may have behavioural strategies that reduce dangers caused by plants."

    To test their theory, the researchers studied how children aged eight to 18 months old reacted when presented with a variety of objects. It took much longer for children to grab plants; objects that were pretended to look like plants also caused a slow response time.

    For parents attempting to spoon some peas into the mouth of their child, this finding should come as welcome relief.

    What was discovered by accident? The answer is penicillin (青霉素). It kills germs. By killing germs, it saves lives. Suppose you are sick. You go to a doctor. She examines you. She says you have a "staph" infection (葡萄球菌感染). She gives you some medicine. You take it. The medicine knocks out the staph. Soon you are well. Before penicillin, this would not happen. Staph was almost sure death.

    Everyone wanted a medicine. Laboratories worked day and night. They grew the staph in small dishes. Then they tried to kill it. Nothing worked.

    The laboratory dishes had covers on them. They kept things from falling into dishes. Molds (霉菌) were a big worry. They are always in the air. You can't see them. They're too small. There are thousands of different molds. Molds can make an experiment fail. That's why dishes are covered.

    Dr. Alexander Fleming was working to kill the staph germ. He worked for years. One day he took a cover off a dish. He looked inside. There was a thick growth of staph germ. There was also some mold. Then he saw something strange. Where the mold was, there was no growth of staph. This is what Fleming probably thought. "By accident, I found a mold to kill the dreaded staph."

    This is how penicillin was found. But here's the real miracle. There are thousands of kinds of molds. But only one kind can kill staph. The mold must have fallen into the dish a few days before. The cover was probably off only a few seconds. In those few seconds the right mold fell into the right dish. Another man might have thrown the dish away. But Fleming was very careful and smart. He understood what the mold did. How lucky the humans were!

    Besides chopsticks vs. knives and forks, there are more differences between Chinese and western dinning.

    Cooking methods

    While westerners boil, fry roast and bake, Chinese use more methods of cooking, like frying, stewing, boiling and steaming. Besides, Chinese cooks cut everything into small pieces, so people don't need knives to cut it but just pick up their food with chopsticks. Westerners cook food in big pieces and serve it with knives and forks for cutting it up.

    Ingredients and spices

    Chinese dishes use many ingredients seldom seen in western cooking, like animal feet, ears, tongues and so on. Chinese usually use animal or peanut oil to fry food; westerners use more butter and olive oil. Chinese cooks like to add spices when cooking, like ginger, pepper, garlic, etc. Western cooks usually use pepper powder, mustard(芥末), and tomato ketchup(番茄酱), etc.

    Serving the dishes

    On the western table, vegetable soup or salad is usually served as the starter, then the main course includes beef, chicken or fish. After the main course, normally some sweet food is served, which can be ice cream, cakes, fruits, etc.

    On the Chinese table, the cold dishes and drinking are first. After that, kinds of meat and vegetable dishes are served, to be followed by soup. Then Chinese usually have rice, noodles or dumplings as main course. At last, Chinese like having fresh fruit such as watermelons and pears after meal. That can make one feel fresh and cool in his mouth and stomach.

    Placing the dishes

    In western dinner, dishes are served in each person's own plate. So each person uses a big plate. In China, dishes are served at the middle of the table for all to share, and each person uses a small plate in front of him or her to hold the food.