If you are sitting, please stand up. Move your legs. Touch your toes if you can. Do anything but sit. New research shows that if you cut down on the time you spend sitting, you might live longer. Sitting less than three hours a day might extend your life by two years. Cutting television time to less than two hours a day can add one point four years to life.

    The human body is designed to move. The fact is just the opposite. Modern lifestyles and office jobs rarely give us the chance to move around. We sit while we're eating; we sit in the car; we sit while we are watching TV. And most of us sit for many hours at work. Sitting is something we do all the time. On average, Americans sit for four and a half to five hours a day. But that does not make sitting good for us.

    Though you may exercise often, that does not mean you can sit for the rest of your waking hours. We can't throw away physical activity. It is extremely important. Even if you exercise for 30 minutes a day, what goes on in the other 23 and a half hours a day is also very important.

    Changes are coming to some offices, especially in the design of desks. A “standing desk” lets people stand while they work. Another new design is called the “treadmill desk”. It is an exercise machine that lets you walk slowly in one place. Even some U.S. schools begin to experiment with desks that are part bicycle to keep children moving.

    Many companies may not buy a standing desk for everybody. However, they may get five standing desks or a treadmill desk for their employees and put them in a certain place where people can go for an hour a day to answer their emails or talk on the phone. Experts suggest some other activities: take a walk at lunchtime; walk to the offices and talk directly instead of emailing colleagues. All these activities may help you live longer.

    Electrical devices (仪器) could soon use power made by human energy. Scientists say they have developed an experimental device that produces electricity from the physical movement of a person walking. British scientist Max Donelan and other scientists in Canada and the United States developed the device.

    The device connects to a person's knee. As the person walks, the device captures energy each time the person slows down. To do this, the device helps with the slowing down movement of the leg. The movements of the walking person push parts of a small machine that produces electricity. Using the device, an adult walking quickly could produce thirteen watts of electricity in just a minute. Donelan says walking at that speed could produce enough power to operate a laptop computer for six minutes.

    There are several possible uses for the device. Developers say it could help people who work in areas without electricity to operate small computers. The device could also be used in hospitals to operate heart pacemakers (起搏器). It could even be used to assist in the movement of robotic arms and legs.

    The experimental version of the device weighs about one and a half kilograms, but it is too costly for most people to buy. But the researchers hope to make a lighter, less costly version. An improved version should be ready in one year.

    The developers hope the device will one day help developing countries. Nearly twenty-five percent of people around the world live without electric power.

    A similar product was invented in 2005 by Larry Rome of the University of Pennsylvania. He created a bag carried on a person's back that also produces power from walking. The knee device does not produce as much electricity as the bag. But the bag requires the walker to carry a load of twenty to thirty kilograms.

    Mary bought a dress in a women's clothing store.She felt very happy about buying the dress until she got home. Then she remembered she had left her purse at the store.It was the third time that month that Mary had forgotten something important.Mary was angry with herself.She said,“Am I losing it?”

    Emma was teaching a class in mathematics at a college.She began to explain to the students how to solve a very difficult problem.She understood it very well.But somehow,at that moment,she could not explain it.Emma said,“I must be losing it.”

    Americans seem to have a lot of concern about losing it.At least that is what you would think from hearing them talk.They use the expression when they feel they are losing control.It can mean losing emotional control.Or losing the ability to do something.Or losing intelligence.

    Word experts differ about how the expression started.Some believe it came from television programs popular in the 1980s.Others believe it began with psychologists,who deal with how people think,feel and act.

    “We Americans have many concerns about controlling our lives.Perhaps we worry too much,”one psychologist said.“In many situations to say you are losing it eases the tension（不安）.”

    It's healthy.And most people who say they are having a problem are not losing it.

    People may feel more like they are losing it when they are “down in the dumps”.Word expert Charles Funk says people have been feeling down in the dumps for more than 400 years.The word dumps probably comes from Northern European countries.The languages of Denmark and Norway both have similar words.The words mean to fall suddenly.Americans borrowed this saying.And,over the years,it has become a popular way of expressing sadness.

    Having a job is great, I have learned. It means I can afford things such as a place to live and daily meals. And with an above-average job, I can afford a car and occasional overseas vacations.

    However, I also understand how difficult it is to have a below-average job, having had many of them before. It's frankly pretty awful. Owning a car was out of the question – I could barely afford to ride the subway.

    So, I decided to go to university and get a degree.

    Later, I emailed my details to every company and government institution with an online careers page. I even printed my resume and handed it out in what seemed like hundreds of office buildings.

    One summer during university, my cousin and I helped out at my uncle's business, fixing roofs, although the only thing I got out of that was back problems.

    That same year, I got a job at a plumbing(管道工程) company, which I was terrible at. It was no surprise when I was asked to leave that job after only four days.

    A lot of people today believe the problem of unemployment in my generation is our fault. Some accuse us of being lazy or feeling too entitled(有资格的). At the same time, some people accuse members of my generation of having a sense of “specialness” that has led us to believe we can all be astronauts, movie stars or singers if we put our minds to it. Also, a few of them think that we would all be happily employed if we would only learn trades or become software engineers, because those people make the most money.

    I realize that not everyone can go into space, star in Hollywood movies or fill stadiums with fans, however. I also think not everyone can make a good electrician or design advanced computer software – I know I can't. Everyone is good at something, but no one is good at everything. It took me hundreds of rejection emails to realize that I had to focus on finding a job where I could actually be successful.

    And now, I finally have that job. All it took was several years of desperation, failure and an honest assessment(评估) of my personal value in the job market.

    It's not the best start, but it's not bad for a start too.

    Last year, I lived in Chile for half a year. I lived with a Chilean family and had the responsibilities of any Chilean teenager. I had good days and bad days I didn't understand.

    Chuquicamata, my host community, is a mining camp. When I arrived there, I was scared. It was so different from what I was used to. There were lots of dogs on the streets, and there was no downtown, few smoothly paved streets, and little to do for entertainment. Rain was not seen very often, earthquakes and windstorms were frequent.

    I had studied Spanish for two and a half years and was always one of the best students in my class. But in my first week in Chile I was only able to communicate and needed one person to whom I could explain my shock. I couldn't speak the thoughts in my head and there were so many.

    Most exchange students experience this like me. Culture shock presents itself in everything from increased aggression towards the people to lack of appetite (食欲). I was required to overcome all difficulties.

    As time passed, everything changed. I began to forget the words in English and to dream in Spanish and love Chilean food. I got used to not depending on expensive things for fun. Fun in Chuquicamata was being with people. And I took math, physics, chemistry, biology, Spanish, art, and philosophy.

    But the sacrifices were nothing compared to the gain. I learned how to accept and to succeed in another culture. I now have a deeper understanding of both myself and others.

    I study English literature at university and have always been proud of Britain's literary heritage(文学遗产). Some British authors that you may have heard of are Charles Dickens and Jane Austen. These writers are famous all over the world because their books have been translated into many different languages. In the UK, their novels are celebrated as some of the best that have ever been written. We say that these novels are "classic" because they are still read and enjoyed years after their publication.

    I read classic novels because they are part of my university lessons but also because I enjoy them. They can teach you a lot about how people used to live and what society was like in the past. Novels like Hard Times by Charles Dickens remind us of the poverty in London during the Industrial Revolution while Jane Austen's fiction shows us what family life was like in the 18th century.

    Classic novels usually have memorable stories land interesting characters. One of my favourite books is Charles Dickens Great Expectations. It is about a boy called Pip who suddenly receives a lot of money from a mysterious supporter. As he grows up, his character changes: he becomes quite selfish and mean. Another important character is Miss Havisham. When she was young, her fiancé ran away on their wedding day. She lives in a dark house and still wears her wedding dress. She is a fascinating character, both sad and scary.

    Reading classic novels enriches my knowledge and life experience. And it has become part of life.