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 spring season brings warm weather, flowers and other changes for people to enjoy. For some restaurant cooks, the most exciting spring arrival is ramps.

    Ramps are a wild plant in the eastern mountains of North America. They are one of the first plants that grow in the spring, usually between April and May. They are recognized(意识) by their red stem(茎), and two long and wide green leaves. They are also famous for their strong taste, similar to onions(洋葱).

    Ramps are not as well-known as other vegetables, but they have a long history in the United States. In the Appalachian Mountains, ramps have been an important food for a longtime. During spring, it is common for small towns in the Appalachian area to hold large ramp dinners for the community.

    However, over the last 30 years, ramps popularity has grown quickly. They are now a highly-desired vegetable for many nice restaurants in cities like New York and Washington D.C.

    One reason the plant is popular is that it grows in the wild. It is difficult to grow them on farms. Most restaurants get them from foragers, who collect ramps by searching forests for some small pieces of land where they grow. Ramps have a short season. Within a few weeks of full growth, the plant is done for the year. This shot life is some reason for their popularity.

    And that popularity could lead Io their disappearance from Earth. In 1995, the local government in Quebee, Canada, stopped people selling the plant to businesses in order to protect the plant against being over-dug.

    The season is short, but it has not ended yet. If you are in the right place, you still have time to try a taste of ramps yourself.

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    I'm the engine that keeps you working, and I'm here to share some of my secrets.

    I have 100 billion nerve cells (神经细胞), so you need to consider before you blame (责怪) me for not being so fast enough. It's not really my fault: information travels through me too fast and sometimes I can't keep all of it.

    The Internet is making me weak. A study found that you've been relying more on the Internet. That means I'm going to forget more over time. Scientists have been worried that our ability to think is being lost.

    In general, I'm about ten percent larger in men than women. It doesn't make men smarter. It just lets me control their different bodies. Actually, it's more common for women to get angry, but men can't focus on a thing well. They usually have language difficulties.

    Your mobile phone scares me. A new study showed that more than one hour of mobile phone use can get me in trouble. Mobile phone radiation (辐射) might cause me to be in a worse situation.

    Some parts of me never sleep. It's important for you to get a good night's sleep. Sleep helps to improve memories. In fact, when you are asleep, some parts of me are still working hard on my duty.

    Besides, laughter is really the best medicine for me. So remember to laugh more for my better situation.

    What's sleepwalking(梦游)？Sleepwalking usually happens in the first few hours of sleep. Not all sleepwalkers walk when they are sleeping. Some just sit up or stand on the bed. Some even get up and walk around for a few minutes or half an hour. Some do things as if they were awake, but in fact they are not!

    Sleepwalkers' eyes are open and they usually go back to beds by themselves. But they won't remember it the next morning.

    About 15% of kids sleepwalk. Sleepwalking sometimes happens when a person is ill or worried, or doesn't get enough sleep. If sleepwalking happens often, you should see a doctor. If it doesn't, you don't need to worry. Here are some ways to help stop sleepwalking:

    Listen to some music and relax before going to bed.

    Go to bed at a regular time every night. keep your bedroom quiet and dark when you try sleeping.

    Don't drink a lot of water in the evening and be sure to go to the bathroom before going to bed.

    Bruce collected the papers Clive collected the cans

    And Mort tied them with string And Dean washed them all clean

    Jason helped Bruce carry the papers Ruby helped Clive carry the cans

    All the way to the recycling(回收) bins All the way to the recycling bins

    When we recycle, we help the plants

    We help the creatures, from eagles to ants

    We help make the world a healthier place

    For one and for all in the human(人类) race