A hobby can be almost anything that a person likes to do in his free time. Hobbyists raise pets, watch birds, paint pictures, play the piano and grow flowers. They also go to concerts, climb mountains, go fishing, skate and swim. They collect everything from books to butterflies and from boxes to stamps.

    People follow hobbies because these activities offer enjoyment, friendship，knowledge and relaxation. Sometimes they even make money by following a hobby. Hobbies help people relax after hard work, and provide a balance between work and play. Hobbies also offer interesting activities for persons who are retired. Anyone, rich or poor, old or young, can follow an interesting hobby.

Hobbies can also help a patient to keep healthy. Doctors have found that hobbies are useful in helping patients (病人) recover from illness. Hobbies give patients who can't move around something to do, and provide interests that keep them from thinking about themselves. Many hospitals treat (治疗) patients by having them take up interesting hobbies. Anyone, old or young, sick or well, rich or poor, can follow a good hobby, in spite of his age, health or money.

    In early times, most people were too busy making a living to have many hobbies. But some persons who had spare time did enjoy hobbies. People today have more time than ever before for hobbies. Machines have now reduced much time that people must spend on their jobs. More people retire at an earlier age than before. Those who have developed hobbies never need to worry about what to do with their newly-found free time hours.

    Sir William Osler, a famous Canadian doctor expressed the value of hobbies by saying, “No man is really happy or safe without a hobby. ”

      The Internet, mobile phones and Ipads are part of our lives now. Technology is greatly affecting all ways of our lives, from the ways we work to the ways we play. And it even causes a number of social problems such as cloning humans.

      We have had lots of technology and it has changed our lives a lot. There is no doubt that humans will continue to use more and more technology. Here are some examples of modern technology that will change our ideas and will affect our lives greatly.

     Global positioning system (GPS) (全球定位系统)

      It's a system that uses radio signals from satellites to show exact information. It tells you where the user is on the earth in all weather conditions. It's made up of three parts: satellites, control equipments(设备) on land and receivers.

     Space Technology

      Russian and American scientists have worked together for the international Space Station (ISS) for a long time. They hope the ISS will provide a long-lasting lab. Such a lab will bring humans limitless (无限的) advantages. It's even hoped that one day space technology will take humans to their new houses in space.

     Underwater Robot

     Hercules is a kind of underwater robot with some high technology equipments. It will be used to look for ancient ships which were destroyed into the deep sea during their journey long ago.

     The world is changing so quickly that it's hard for us to catch up with all the new inventions because they seem to come out every month. It's important for us to learn about new technology and the role that it plays in our lives. So we should be willing to accept modern technology, or we will fall behind the times.

    A computer can get very hot when it works on a lot of programs. It can cost a lot to cool the computer. So some scientists want to know what would happen if the heat from the computer could be used.

    Large Internet companies such as Google and Microsoft have thousands of computers. As these computers deal with information， they produce lots of heat， so they need huge cooling systems. These systems send the heat into the air.

    A company in Holland thinks paying to make the computers work and then paying again to cool them are a waste of energy. So the company developed a special device—the e-Radiator.

    Boaz Leupe， head of the company， says that e-Radiator works as a heating system and saves money. He explains that the energy is used twice—once to heat the home and once to cool the computer and that the users don't have to pay to cool their computers.

    Five homeowners in Holland are testing the heating system in their homes.

    “We pay for the computer using， so， in that way， homeowners get heating for free.” Boaz says.

    Jan Visser is one of the homeowners. “If you use the computer more， the e-Radiator producers more heat，” he says， “It cannot provide enough heat if you don't use your computer often.” But he is ready to try it. It's a great help for his family.

    The company says e-Radiators produce heat temperatures of up to 55℃. It says the system could save its users about $440 a year.

    The Legendary Berlnuda Triangle (百慕大三角): A Mystery No More

    For years, people have believed that an area of the Atlantic Ocean between Bermuda, Puerto Rico and Florida, USA was a dangerous place. They thought planes and boats passing through here were likely to disappear. By 1964, a writer had called the area the "'Bermuda Triangle". The name stuck, and so did the mystery.

    In 1945, five US Navy planes, called Flight 19 took off from Florida and never came back. After they disappeared into the Bermuda Triangle, different ideas had begun to spread that the area was a dangerous place. Even before this famous flight, several ships had disappeared in these waters. People had many different ideas about why this appended. Some people even believed that a huge octopus (章鱼) was responsible!

    However, scientists believe that weather is part of the problem. Unusually shaped clouds above the area create strong winds that go down into the water, creating huge tsunami (海啸) waves that can take down boats or low-flying planes. And many researchers believe that there's no mystery, at all Ship goes down and plane accidents happen all over the world. It just seems to happen more in the Bermuda Triangle because there's more traffic.

    The Bermuda Triangle is also one of the deepest areas of the Atlantic, with some areas being 8 km (5 mi.) deep. So, remains are hard to find which makes the disappearances seem even more mysterious. In 2011, the Flight 19 planes were found, showing that they didn't completely disappear. But no matter how much evidence（证据） there is that the Bermuda Triangle is no more dangerous than any other part of the ocean, many still believe that you mustn't go there.

    Thousands of years ago, people didn't know that the Earth moved. They thought the sun really did move across the sky. The Greek god Helios was said to drive the sun across the sky with his chariot (战车). But now, the way people think has changed. Nowadays, it is the sun that drives a "chariot" around the sky.

    What do I mean by this? Well, quite simply, there is now a plane (or "chariot") that is powered by the sun. It has special parts on its wings. These parts absorb (吸收) power from the sun. They absorb so much power that the plane can still fly even at night. In Greek mythology (神话), Helios had to take a break at night. It seems we're finally even more powerful than the gods themselves.

    This plane is called Solar Impulse. It will fly across the US in May. This is very important for the future of the world.

    Why is solar energy (太阳能) important? Well, other kinds of energy are known to cause problems. If you live in China, you've probably noticed the pollution. This is caused by burning coal and gas to make energy. The heat and chemicals created by burning these things give us power. But if we use power from the sun, we don't have to burn anything and there will not be any pollution.

    Solar energy is not entirely ready yet. It needs to be improved. But the best thing about it is that, unlike coal and gas, it doesn't run out. The Solar Impulse plane could pretty much keep flying forever. Of course, the sun's light will eventually run out too one day, but not for another 5 billion years. That's a pretty long flight.