E

    The Earth is our home; we must take care of it. This means keeping the land, air and water clean. Pollution is a dirty word. To pollute means to make things unfit or unclean to use. Pollution comes in many ways. We see it, smell it, taste it and drink it. Pollution is beginning to threaten (威胁) our health, our happiness and our life. Man has been polluting the earth from the time he first made fire, washed his clothes in the river and threw his waste on the ground. When land was used up or water became dirty, men moved on to another place. At first, the problem was not so serious because there was plenty of clean air, land and water. There weren't so many people then and their wants were fewer. All the dirty things could be absorbed (吸收) by nature and soon covered over. But this is no longer true. The increase of population and the development of industry(工业)have changed that. Man is slowly poisoning (毒害) his environment. Through the use of poison, man has polluted the land, killing the animals. By putting dirty water and chemicals into rivers and lakes we have polluted our drinking water, killing the fish.

    Our increasing population is part of the problem. More people, more waste.

    Where is this all to end? Are we turning the world into a big rubbish dump (堆存处), or is there any hope that we can get rid of (摆脱, 除去) the pollution? Luckily, millions of people have been warned of the danger of pollution. Large numbers of people are now working hard to bring pollution under control.

C

    In the future, your automobile will run on water instead of gas! You will be able to buy a supercomputer that fits in your pocket! You might even drive a flying car!

    For each prediction(预言) that has come true today, several others have missed by a mile. Many of these predictions didn't consider how people want to use the technology, or if people really needed it in their lives or not. Let's look at some predictions from the not-too-distant past.

    Robot helpers

    Where's the robot in my kitchen? Nowhere, of course. And he's probably not coming any time soon. Robots do exist today, but mostly in factories and other manufacturing environments.

    Back in the 1950s, however, people said that by now personal robots would be in most people's homes.

    So why it hasn't happened? Probably because robots are still too expensive and clumsy. And maybe the idea of robots cooking our dinners and washing our clothes is just too weird. At home we seem to be doing fine without them.

    Telephones of tomorrow

    In 1964, an American company introduced the video telephone. They said by the year 2000 most people would have a video phone in their homes. But of course the idea hasn't caught on yet.

    Why? The technology worked fine, but it overlooked something obvious: People desire for privacy. Would you want to have a video phone conversation with someone after you just stepped out of the shower?

    Probably not—it could be embarrassing! Just because a technology available(可利用的) doesn't always mean people will want to use it.

    Flying cars

    And finally, how about that crazy prediction of the flying car? It's not so crazy any more! But a flying car remains one of the most fascinating technology ideas to capture our imagination. Keep watching the news or perhaps the sky outside your window to see what the future will bring.

    There are some easy things you can do to protect the environment and the earth. Choose ideas from the list or come up with a few of your own.

    ·Plant flowers, grass or trees.

    ·Whenever you visit a park or beach, take away what you bring there-keep rubbish in a bag until you can put it in a dustbin.

    ·Turn off the lights, TV sets when you leave the room. This saves a lot of electricity.

    ·Turn off the tap when you brush your teeth. You can save some water by not letting it run. Also, use a glass cup instead of a paper cup because this saves paper.

    ·Keep the doors and windows closed in winter to keep cold air in.

    ·Give your old books and magazines to a library instead of throwing them away.

    ·Give your old clothes to poor children you know instead of throwing them away.

    ·Use both sides of paper.

    ·Stop pouring dirty water into the rivers or lakes nearby.

    ·Encourage all your friends to do the same things you do to help protect the earth.

    You don't have to wait until Earth Day to do these things. Make every day Earth Day.

    If everyone makes a contribution to protecting the environment, the world will become much more beautiful.

    In most parts of the world, many students help their schools make less pollution. They join environment clubs. In an environment club, people work together to make our environment clean.

    Here are some things students often do.

    No-rubbish lunches. How many lunch bags do you throw away after lunch? Environment clubs ask students to bring their lunches in bags that can be used again. Every week they will choose which classes make the least rubbish and report them to the whole school.

    No-car day. On a no-car day, nobody comes to school in a car including the students and the teachers. Cars give pollution to us, so remember:

    Walk, jump, bike, or run!

    Use your legs! It's lots of fun!

    Turn off the water! Do you know that some toilets can waste twenty to forty cubic (立方) meters of water an hour? In a year, that would fill in a small river. In the environment clubs, students repair those broken toilets.

    We love our environment. Let's work together to make it better.

    Is there intelligent (有智力的) life on other planets? For years, scientists said "no" or "we don't know". But today this is changing. Seth Shostak and Alexandra Barnett are astronomers (天文学家). They believe intelligent life exists (存在) somewhere in the universe. They also think we will soon contact these beings (人；生物).

    Why do Shostak and Barnett think intelligent life exists on other planets? The first reason is time. Scientists believe the universe is about 12 billion years old. "This is long enough for other planets to have intelligent life," say Shostak and Barnett. The second reason is size—the universe is huge. "Tools like the Hubble Telescope (哈勃望远镜) have shown that there are at least 100 billion galaxies," says Shostak. "And our galaxy, the Milky Way, has at least 100 billion stars. Some planets going around these stars might be similar to Earth."

    In the past, it was hard to look for signs of intelligent life in the universe. But now, powerful telescopes (高倍望远镜) allow scientists to discover smaller planets. These planets might have intelligent life.

    Have beings from space already visited Earth? "Probably not," says Shostak. However, intelligent beings may contact us in other way, such as radio signals (信号). In fact, they may be trying to communicate with us now, but we don't have the right tools to receive their messages. However, this is changing. By 2025, we could make contact with other life forms in our universe and we might help each other.