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.

    The evening of September 29, 2011, China launched (发射) its first space lab module Tiangong-1 at the Jiuquan Satellite Launch Center in northwestern China.

    President Hu Jintao praised the success of China's first space lab module Tiangong-1, and shook hands with the staff of the Beijing Aerospace Flight Control Center.

    Premier Wen Jiabao and He Guoqiang also shook hands with the staff at the Jiuquan Satellite Launch Center to congratulate on the success.

    Tiangong-1, which is plannedtoconnect with the Shenzhou-8 spacecraft later this year, will get ready for building China's first space station.

    During its two-year service life, Tiangong-1 will mainly carry on four tasks, such as experiments of autonomous rendezvous(自主交会) and connection with the Shenzhou-8, -9, and -10 spacecrafts in the coming launches, which is going to set up the country's first space lab, according to Wu Ping, spokesperson for China's National Space Administration.

    According to the plan for China's manned space program, the Shenzhou-10 will be a manned spacecraft that is going to carry a female Chinese astronaut.

    Tiangong-1 is expected to become China's first space laboratory when it connects to the above mentioned spaceships.

    The human brain weighs about 1.4 kilograms, but it can hold much more information than most computers．However, there is another difference between humans and computers．Computers don't forget information they are given, but humans often do．No one remembers everything, and luckily we don't usually have to．But everyone can improve their memory if they want to．Here are some suggestions．

    Try to use new information immediately．For example, if you meet someone who says "Hi! I'm Carlos．"Don't just say "Hello．" Repeat the person's name．Say "________"

    Break a big number into smaller parts． For example, it's hard to memorize (记忆) 109244153．But if you break it into three parts  109/244/153--it becomes easier．

    Write out what you need to remember over and over again．This will help you keep it in mind longer, especially for memorizing formulas (公式) or facts．

Always review information．If you bring what you've learned back to your mind, it becomes easier to remember． For example, before you go to sleep, it's a good idea to review the new things you learned that day．

    Discuss with a friend．It is always easier to remember things through discussions．You can have a discussion about what's right and what's wrong, and it will lead to the right answer．

    Never tell yourself that you have a bad memory．You can always do something to help improve your memory．And everyone's memory gets better if they use it often enough．

    All the suggestions are helpful．If you follow them, you are certain to improve your memory．

    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. "

    Technology is developing fast and it has become an important part of our life. Then what will the world be like in the future?

    3—D food will be both delicious and nutritious(有营养的). We can use 3—D printers to print some basic materials.    ①    And we can go further. Scientists belive that we just need to turn on a printer in the kitchen and then we can enjoy our favourite food whenever we like.

         ②      5G network will allow many more people to get information. Big companies like China Mobile and China Unicom will start to offer 5G. It is said that promises download speeds 10 to 20 times faster than 4G. For example, we can download a film within just 1 second. But with a 4G network, it takes a few minutes. There will be much bandwidth (带宽) and we can get unlimited (无限的) information.

    Underwater cities will provide more space. The earth is becoming more and more crowded. We may turn to underwater homes, which will be built as low as 15 of the sea can be used to provide power for the homes.

         ③      For us common people on the earth, the dream of travelling around space will come true. In the coming years, spacecraft will be as popular as buses, trains and planes. We can leave our home and enter space to take an adventure (冒险). And even we will get used to living there.

    A robot will be a part of life.  Robots can do many of the same things as we humans do like driving cars. But they will be used in other areas as well. They will be able to think. They can tell the difference between right and wrong. They can feel       ④        In a word, just as Jules Verne said, "Anything one man can imagine, other men can make real."

    A thirsty crow(乌鸦) comes across(偶然遇到) a bottle of water, but the water level is out of its reach. The bird then drops some stones into it and gets the water.

    "It's just a story," you may think. But new research has found that crows' brains may sometimes be better than those of 6­year­old children.

In a recent experiment, American scientist Corina Logan and her team caught six crows to test them. The crows and children had to choose between two sets of tubes(试管). They had to drop stones in and get water.

    With the red set, when they dropped a stone into a wide tube, the water level raised in a connected narrow tube. The blue set of tubes, however, had no connection between them.

    Children aged 7 to 10 were able to learn the rule. Children aged 4 to 6, however, failed. Five of the six crows failed the test. But Kitty, a 6­month­old crow, passed it. She put most of the stones into the red tubes.

    So, could a bird be more clever than a kindergartner? Don't be too quick to say no.