Today, we are told, children don't spend enough time in the fresh air. Many of them are addicted to screen on a computer or a TV—they seem to be living in a virtual world. They have lost touch with nature.

    But now 400 organizations in the UK, from playgroups to the National Health Service, are encouraging children to have some “wild time”. They want kids to swap at least 30 minutes of watching TV or playing computer games for time playing outside. Activities such as building dens, climbing trees, rummaging for conkers and playing hide and seek are just some of the things kids can do. Even if they live in a city, they can go on adventures in the garden or the park.

    Children often need a helping hand from mom and dad. They need to be shown what to do and where to go. Andy Simpson from National Health Service says, “We want parents to see what this magical wonder product does for their kids' development, independence and creativity, by giving wild time a go”.

    So despite the complicated world that young people grow up in now, it seems that going back to basics and experiencing “nature's playground” is what modern children need. David Bond from Project Wild Thing says, “We need to make more space for wild time in children's daily routine, freeing this generation of kids to have the sort of experiences that many of us took for granted”.

    This might sound a bit old fashioned to you or maybe, like me, it's made you think about sticking on your boots, getting outdoors and reliving your childhood. There is no age limit on enjoying yourself!

    “Have a nice day！” may be a pleasant gesture or a meaningless expression. When my friend Maxie says “Have a nice day” with a smile, I know she sincerely cares about what happens to me. I feel loved and safe since another person cares about me and wishes me well.

    “Have a nice day. Next！” This version of the expression is spoken by a salesgirl at the supermarket who is rushing me and my groceries out the door. The words come out in the same tone (腔调) with a fixed procedure. They are spoken at me, not to me. Obviously, the concern for my day and everyone else's is the management's attempt to increase business.

    The expression is one of those behaviors that help people get along with each other. Sometimes it indicates the end of a meeting. As soon as you hear it, you know the meeting is at an end. Sometimes the expression saves us when we don't know what to say.  “Oh, you just had a tooth out? I'm terribly sorry, but have a nice day. ”

    The expression can be pleasant. If a stranger says “Have a nice day” to you, you may find it heart­warming because someone you don't know has tried to be nice to you.

    Although the use of the expression is an insincere, meaningless social custom at times, there is nothing wrong with the sentence except that it is a little uninteresting. The salesgirl, the waitress, the teacher, and all the countless others who speak it without thinking may not really care about my day. But in a strange and comfortable way, it's nice to know they care enough to pretend they care when they really don't care all that much. While the expression may not often be sincere, it is always spoken. The point is that people say it all the time when they like.

    Feifei, an 11-year-old boy from Xuzhou, Jiangsu Province, suffered from a sudden acute eye disease which has almost led to blindness. The disease was caused when he overused his eyes during the winter vacation, during which he played computer games for continuous 10 days and nights.

    Many youngsters in China nowadays are increasingly addicted to computer games and other electronic products. This is followed by a series of health problems, with the most typical case being myopia, or nearsightedness.

    According to the latest research report released by the World Health Organization (WHO),the myopia rate among Chinese teenagers ranks first in the world—70 percent of high school and college students. The rate is nearly 40 percent in primary school students, while it is only 10 percent for their peers in the United States.

    There are at least 10 million people in China with severe myopia, and they are likely to get pathological myopia（病理性的近视） in middle age. Pathological myopia can't be treated with glasses or surgery, and it is one of the biggest factors that lead to blindness, Xu Xun, an expert at Shanghai General Hospital, pointed out.

    Experts explain that two major factors lead to the high rate of myopia among Chinese people. One is high academic pressure, and the other one is excessive use of electronic devices over a long period of time. Genetics, on the other hand, are not the main reason, as only 20 percent of Chinese people had myopia in the 1960s.

    "Teenagers are now faced with severe academic pressure, which means they often study without natural light. This increases their risk of becoming nearsighted," Xu said. Experts suggest that youngsters maintain a proper balance between study and rest so as to protect their eyesight, and parents should play an active role in the process.

    The meaning of silence varies among cultural groups. Silences may be thoughtful, or they may be empty when a person has nothing to say. A silence in a conversation may also show stubbornness, uneasiness, or worry. Silence may be viewed by some cultural groups as extremely uncomfortable; thus efforts may be made to fill every gap(间隙) with conversation. Persons in other cultural groups value silence and view it as necessary for understanding a person's needs.

    Many Native Americans value silence and feel it is a basic part of communicating among people, just as some traditional Chinese and Thai persons do. Therefore, when a person from one of these cultures is speaking and suddenly stops, what may be implied(暗示) is that the person wants the listener to think about what has been said before continuing. In these cultures, silence is a call for thinking.

    Other cultures may use silence in other ways, particularly when dealing with disagreements among people or in relationships of people with different amounts of power. For example, Russian, French, and Spanish persons may use silence to show agreement between parties about the topic under discussion. However, Mexicans may use silence when instructions (指示，命令) are given by a person in authority rather than be rude to that person by arguing with him or her. In still another use, persons in Asian cultures may view silence as a sign of respect, particularly to an elder or a person in authority.

    Nurses and other care-givers need to notice the possible meanings of silence when they come across the personal worries their patients may be experiencing. Nurses should recognize their own personal and cultural construction of silence so that a patient's silence is not disturbed too early or allowed to go on unnecessarily. A nurse who understands the healing(治愈) value of silence can use this understanding to help in the care of patients from their own and from other cultures.

    A unique experience awaits you at the Centre for Alternative Technology on the edge of the beautiful Snowdonia National Park.

    Over thirty years ago a group of people decided to try out alternative technologies. They chose a remote empty place, where rock used to be dug from the ground, as their base. Here experiments offering solutions to the world's energy problems were carried out, and nowadays many of these ideas have become common practice. You can experience all these for yourself in just one day with us, and then take away what you have learned and put it into practice at home. Be assured it will help you save on your household energy costs!

    Your visit to us begins with a ride up a steep 60-metre hillside on a railway which is worked by using the weight of water. At the top of the mountain you will enjoy beautiful views to the distant coastline. Then interactive displays show the power of wind, water and sun, while showing you what can be done in an ordinary household to reduce your influence on the planet.

    There was no soil when the project was started, so we created our organic gardens using our own home-made soil. You can enjoy woodland walks or even notice spring flowers growing on the roofs of environmentally-friendly buildings.

    In 2006 we opened our new eco-adventure playground for children, and we also run workshops where they can make models and become inventors of the future by putting wind, water or solar power into their own designs.

    The Centre for Alternative Technology is open all year round and has good rail, road and cycle links. In fact we offer a 50% reduction on the admission price if you arrive by bicycle. There is wheelchair access for disabled visitors—telephone us in advance if you would like assistance.

    Why do we dream? It's a question researchers have been studying for years. Now new research suggests that some dreams may result from the brain's effort to keep learning, even as we sleep.

In a study in Boston,100 volunteers were trained for an hour on a maze(迷宫). They tried to find their way through the difficult puzzle as quickly as possible. Then half of the volunteers were allowed to sleep for 90 minutes. The other half stayed awake, reading or relaxing. The ones who slept were asked to describe their dreams when they woke up.

    After the rest, the volunteers were asked again to solve the maze. Those who hadn't slept showed no improvement or did even worse after the break. Sleepers who didn't report any maze­related dreams did better but showed only a little improvement. However, four nap­takers who reported dreaming about the maze showed a surprising improvement. They scored 10 times higher after sleeping and dreaming about the maze.

    Even though the number of dreamers was small, the researchers noted that the gap in learning between the dreamers and non­dreamers was so wide that the finding was significant(有意义的).

The dreamers had all performed poorly on the test before dreaming about it. That suggests that struggling with a task might be the trigger that leads the sleeping brain to focus on it and work on how to deal with it.

    "It's almost as if your brain is going through everything that happened today," Dr Stickgold, a scientist at Harvard Medical School, said. "The things you're obsessed(迷住) with are the ones that your brain forces you to continue to do with."