The Smallest Life Around Us

    Tiny plants and animals live all around us．We cannot see them because they are so small，but they are everywhere. They live in the soil，in the air，and in rivers and oceans．They grow on mountains and in caves．Some live in the ice at the north and south poles; some live where it is very hot．They are found throughout cities and in the country. They grow on other plants and animals．Some are even living on you，on your skin，hair，and inside your body，in your mouth，nose，and all through your body．

    These tiny plants and animals are called microbes．The word microbe is made from two other words：micro，meaning small，and bios，meaning life．So，microbe means small life．

    Microbes have been on earth for a very long time．They may have been the first forms of life to be alive．Today there are more microbes in the world than all other living things．

    People did not know microbes had existed（存在） long．They were too small for them to see．But people did see many changes in their world﹣important changes．And they did not know what caused them．They saw food that they kept too long change color and begin to smell bad．They saw cuts and wounds grow red and painful and become worse. They saw old plants and leaves and trees crumble apart on the forest floor and disappear into the soil．Such changes were a natural part of the world，but people did not understand them．They did not know these changes were evidence(证据) of tiny plants and animals growing all around them.

    Noise pollution is doing much harm to our health now. Noise，in fact，is unwanted sound and is a kind of invisible (无形的) killer. More and more students enjoy listening to music very much. When they listen to MP3 players, they like to turn up the volume (音量). Some people love listening to loud music. Furthermore, while watching TV, they keep the volume up. But they haven't realized that the noise is weakening their hearing. In fact, the noise not only influences each member in the family, but also makes a difference to the comfort of neighbors.

    Noise pollution is a source of increasing misery (痛苦) to people in our society. If people are often disturbed by it, they may feel uncomfortable or upset. What's worse, the noise can make people mad sometimes. If a worker works in a printing factory for too long, his/her hearing loss is much faster than a common person working in a quieter environment. So everybody must pay more attention to noise pollution. Generally speaking，the following four types of noise should be watched out for：

    Noise in the street

    Construction site (建筑工地) noise

    Noise at work

    Transportation noise

    I think the local department (部门) should take measures to control the noise levels, but it's everybody's duty to keep a quiet environment.

    You can not see any object unless light from that object gets into your eyes. Some of the things you see give off light of their own. The sun, the stars, a lighted lamp are examples that can be seen by their own light. Such things are luminous. Most of the things you see are not giving off light of their own. They are simply reflecting light that falls on them from the sun or some other luminous bodies moon. For example, does not give off any light of its own. It is non-luminous. You see it because sunlight falls on it and some of it reflects in our direction. So moon light is only second hand sunlight.

    When you look at a book, it sends to your eyes some of the light which falls on it, and you see the book. If light could be kept out from where you are so that there would be no light for the book to reflect, then you could not see the book even with your eyes wide open.

    Light travels so fast that the time in which it travels from the book you are reading to your eyes is so short as if there were no time at all. Light reaches us from the moon, which is about 380 000 kilometers away, in only a little more than a second.

Where would you like to stay when you go on a vacation? What kind of hotel would you like to choose? Different people have different ideas. In fact, there are all kinds of special places to stay when you go on a vacation. There are hotels, motels, youth hostels, B&Bs (bed-and-breakfast), home stays, and more. Each is for a different kind of people. If you travel by car, a motel is good for you. You can park your car outside your room. A youth hostel is good for young backpackers (背包客). A B&Bs might be best for couples (夫妻) or anybody who doesn't like being noisy.

    For people who like reading, the library hotel in New York is a must-see. Each of the hotel's 60 rooms is full of books. In fact the hotel has over 6, 000 books in all. If history is your thing, the 9th floor is for you. If you are interested in math and science, you can stay on the 5th floor. Artists will feel at home on the 7th floor. The Poetry Garden is on the 14th floor, and there is a cozy sofa in it. You can sit on the sofa and enjoy reading a good book or relax outside in the Poetry Garden.