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    Body language is one of the most powerful means of communication, often even more powerful than spoken language. People around the world show all kinds of feelings, wishes and attitudes that they might never speak aloud. It is possible to ―read‖ others around us, even if they do not want us to catch their unspoken communication. Of course, body language can be misread, but many gestures and actions are common.

    The most common facial expression is, of course, the smile – its function is to show happiness and put people at ease. It does not always mean that we are truly happy, however. Smiles around the world can be false, hiding other feelings like anger, fear or worry. There are unhappy smiles, such as when someone ―loses face‖ and smiles to hide it. However, the general purpose of smiling is to show good feelings.

From the time we are babies, we show unhappiness or anger by frowning (皱眉头). In most places around the world, frowning and turning one's back to someone shows anger. Making a fist (拳头) and shaking it almost always means that someone is angry.

How about showing that I am bored? Looking away from people or yawning will, in most cases, make me appear to be uninterested. However, if I turn toward and look at someone or something, people from almost every culture will think that I am interested.

    Being respectful to people is subjective, based on each culture, but in general it is probably not a good idea to give a hug to boss or teacher. In almost every culture, it is not usually good to stand too close to someone of a higher rank (等级). Standing at a little distance with open hands will show that I am willing to listen.

    With so many cultural differences between people, it is great to have some similarities in body language. We can often be wrong about each other, so it is an amazing thing that we understand each other as well as we do!

We've talked about snails (蜗牛) and their slow move. But much of the time snails don't move at all. They're in their shells —sleeping .

    Hot sun will dry out a snail's body. So at the least sign of hot sun, a snail draws its body into its shell and closes the opening with a thin cover. Then it goes to sleep. A snail will die in a heavy rain. So whenever it rains, it goes inside its shell house and goes to sleep. A snail can sleep for as long as it needs to. It can take a short sleep. Or it can sleep for days at a time. And it spends all the winter months in its shell, asleep.

    In spring the snail wakes up. Its body, about three inches long, comes out of from the shell. When hungry, the snail looks for food. It can't see very well. Its eyes, at the ends of the top feelers are very weak. But its sense of smell is very strong. It helps the snail to the new greens. Then the snail's little mouth goes to work.

    A snail's mouth is no longer than the point of a pin(针). Yet it has 256,000 teeth! The teeth are so small that you can't see them. But they do their work. If you put a snail in a hard paper box, it will eat its way out. And if a snail wears out its teeth, it will grow new ones.

    Mostly, a snail looks for food at night .But on cloudy days it eats in the daytime. It eats all day long. A snail can go on eating for hours and never feel full.

    Lately, people have entered the forests where chimpanzees live. The chimpanzees have been getting sick because of people's diseases. In addition, people are hunting chimpanzees. Their number is becoming smaller and smaller.

    Chimpanzees live in the plains and forests of Africa. They eat many kinds of foods, from plant leaves and seeds to insects and even other small animals. Chimpanzees' favourite food is fruit.

    Chimpanzees are very clever and they can use tools well. They can catch bugs by using sticks, and break nuts by using rocks.

    The world's forests are much smaller than they were before. Roads were built in deep forests, so people start to enter the forests where chimpanzees live. That may lead to many problems. One problem for chimpanzees is that they can easily catch people's diseases and die.

Chimpanzees are much closer to people than monkeys.

    As it's easier for people to enter forests, they hunt more often. Young chimpanzees are caught to be pets or for scientific research. The young ones are taken away from the forests, and the adults are killed. Chimpanzees are likely to disappear in the future.

    Have you ever wished that your life was like a reality TV show(真人秀节目)? Well, like it or not, things might be this way in the future.

    This is because of Google glasses. Glasses are the latest technology from Google. They have more exciting features(特征)than you could possibly imagine.

    For one thing, people who wear the glasses can shoot videos and record the sounds around them. So if your friend is wearing Google glasses, he or she can record your every move and broadcast live on the Internet for the world to see.

    There is a GPS system in the glasses. So if you get lost you can say" OK, Glass, where am I?", and it will find where you are and tell you where you need to 90.

    Google glasses are a bit like a helpful secretary. You can tell them what you want to write in an e—mail and they will type it for you.

    Since April 16, Google glasses have been on the market in small numbers. But by the end of the year anyone will be able to buy a pair for about 2, 500 yuan.

    Some people are not sure whether they find Google glasses cool or not. When someone is wearing Google glasses, it is not easy to see whether or not they are using them.

    Some people wonder why countries spend millions of dollars on space projects. They want to know how space research helps people on Earth. Actually, space technology helps people on Earth every day. This is called "spinoff technology". Spinoff technology is space technology that is now used on Earth.

    In early space programs, such as the Apollo missions(任务) of the 1960s and 1970s, and in the space shuttle missions today, scientists developed objects for the astronauts to use on the moon and in space. We now use some of these objects every day. For example, we have Quartz clocks and watches with an accuracy of one minute a year. We purify the water we drink with a water filter(过滤器) designed for the astronauts' use in space. The cordless, hand-held tools we use in our homes, such as cleaners, flashlights, drills, and irons came from the technology of these early space programs.

    On cold winter days, we can stay warm with battery - operated shoes and socks, and insulated(绝缘的) coats and jackets. All of these clothes are similar to the spacesuit designs that keep astronauts comfortable in the temperatures of the moon, and are spinoffs from space technology.

    These products are only a few examples of the many ways space technology helps us in our everyday life. No one knows how new spinoff technology from the International Space Station will help us in the future.

    Which is the tallest mountain on the earth? The answer must come fast—MT Everest, at a height of 29,000 feet.

    But that is only on land. For, if you were to measure (测量) from the bottom (底部) of the ocean. The tallest mountain in the world will probably be Mauna Kea in Hawaii. It is more than 15,748 feet under the sea and another 13.779 feet above it.

    As US scientist Cindy Lee Dover points out that the seafloor is the largest and least known place on the earth. We know more about Mars (火星) and Venus (金星) and the back side of the moon than we know about the seafloor.

    Some people have travelled to the deep water of the ocean to try to find all kinds of unknown animals and plants living in the deep water. Even scientists know very little about them. Many of them perhaps do not even have names. Some of the names given by scientists to newly discovered (被发现) animals are really funny. Among them are the spaghetti worms (意大利面蠕虫), named as such it is found in a tangle (缠结), it is often difficult to make out where one ends and another begins! Just like spaghetti.