A recent study found people's lives are made shorter in North China. It is showed the life expectancy(平均寿命) had been cut down by 5.5 years there. Researchers（研究者）think that the heavy air pollution in China should be to blame(承担责任). It's really the truth. Our government has already done something. However, it doesn't seem to work so well.

    “Air pollution in China is doing harm to people's health. The harm is much more serious than we can imagine,” said Chen Yuyu of Beijing University, one of researchers of this study.

    Dirty air brings serious problems in North China. In January this year, the air pollution was worse than that in other places. That was caused by rising temperature and waste gas（气体）from coal heating（燃煤）.

    Chinese government should strongly fight with air pollution. They should think of more proper ways to deal with the problem. People should be encouraged to take buses, ride bicycles or walk, instead of driving cars. The factories that pollute heavily should be closed.

    “We need to improve our environment, although it might be expensive. Protecting our environment means protecting ourselves,” Li Hongbin, another researcher of the study said.

    I am an apple. I'm a kind of sweet1You can find me grow in many places of the world, but I can't grow well in very hot places2 very cold places.

    I am not like my cousins 3and bananas. I am rounder than a pear and bananas are4than me. I am delicious,5people all over the world like to eat me. They can usually eat me6washing me. They can also cook me to 7all kinds of food, sometimes they put me in cans（罐头）to send me to other places of the world. Almost everyone can have 8 to buy me because I'm so cheap.

    I can also help people get9 There is a saying10English: An apple a day keeps the doctor away. Don't you think that I'm very great? I have many vitamins（维生素）inside, they are 11for you. I really wish to make you happy and healthy. so don't forget to 12me as often as possible（尽可能经常地）.

    But I also need your13, if you want to make me taste better, you must14 me well. Thank you for your love. I'll try to grow well and15sweeter. Then you will like to eat me a lot more.

    One morning while Officer Vogel was on his coffee break in a restaurant, a man ran in a yelled. "Officer! A little kid is driving a car down the street!"

    He ran out at once and saw a car going slowly--about 25 miles an hour--but it was going very straight. He jumped into his police car and followed it. When the car was stopped, Officer Vogel looked inside. The driver was a little boy. His name was Rocco Morabiro and was 5. In the back seat was his two-year-old sister. Both children wen crying.

    "I want my mummy!" the boy cried." But she can't get here. I have the car." Then he had an idea." Just a minute." He told Officer Vogel." I can drive. I'll go to get her."

    "No!" Officer Vogel said. "You stay with me!" Then he drove them to the police station and he called their mother. They had many questions for Rocco. The first question was: "Where did you get the car keys?"

    Rocco said. "From the top of the refrigerator." At seven that morning Rocoo's father was work and his mother was sleeping, Rocco saw the keys on top of the refrigerator. He climbed on a chair, and took the keys.

Rocco got into the car and started the engine (引擎). When Rocco's sister heard the engine she ran to the car and cried. She wanted to go with him.

It was 7 a. m.—rush hour—so there was much traffic. Rocco drove one mile in heavy traffic. Then Officer Vogel stopped him.

    Newspapers and TV stations heard about Rocco, and a lot of reporters went to his house. Areporter asked Rocco, "What do you want to be when you grow up?"

    "A truck driver," he said, smiling.

    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 them.

    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 the 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-the size of Mars or the earth-in other solar systems, these planets might have intelligent life.

    Have beings from space already visited the earth? "Probably not, "says Shostak. "It's a long way away. 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. "

    As space science develops, man has learned more and more about space. Space is not only amazing but also dangerous. While working in space, spacemen are facing danger as well as success.

    Scientists have found out that the radiation(辐射) is the greatest danger to spacemen in space. When spacemen are working in space, they are in danger of the radiation from the sun and other stars, which is bad for their health. The harm of the radiation won't be found until their children even grandchildren are born. Some special medicine may work a little, but no really effective medicine has been found so far. Space rubbish is also thought to be a great danger to spacemen. It's reported that there were 9,000 man-made things flying in space. About 30% of these are satellites, 10% are spaceships, and the rest are space rubbish. An explosion(爆炸) in space in 1999 made a cloud of 300,000fragments, each at least 4mm in size. A small piece of these even knocked a spaceship window and caused some damage(损坏).

    Scientists are watching and reporting any possible danger all the time. They are working to deal with space rubbish. Although space is really dangerous, it interests many people on the earth. In the near future, it may become possible for people to spend a few days in a space hotel. People may even choose to leave the earth and live in space in a few years. So scientists are doing everything they can to help improve the space environment.