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    A buld-it-yourself solar still（蒸馏器） is one of the best ways to obtain drinking water in areas where the liquid is not readily available. Developed by two doctors in the U.S. Department of Agriculture, it's an excellent water collector. Unfortunately, you must carry the necessary equipment with you, since it's all but impossible to find natural substitutes. The only components required, though, are a 5'  5' sheet of clear or slightly milky plastic, six feet of plastic tube, and a container— perhaps just a drinking cup — to catch the water. These pieces can be folded into a neat little pack and fastened on your belt.

    To construct a working still, use a sharp stick or rock to dig a hole four feet across and three feet deep. Try to make the hole in a damp area to increase the water catcher's  productivity. Place your cup in the deepest part of the hole. Then lay the tube in place so that one end rests all the way in the cup and the rest of the line runs up — and out — the side of the hole.

    Next, cover the hole with the plastic sheet, securing the edges of the plastic with dirt and weighting the sheet's center down with a rock. The plastic should now form a cone(圆锥体) with 45-degree-angled sides. The low point of the sheet must be centered directly over, and no more than three inches above, the cup.

    The solar still works by creating a greenhouse under the plastic. Ground water evaporates (蒸发) and collects on the sheet until small drops of water form, run down the material and fall off into the cup. When the container is full, you can suck the refreshment out through the tube, and won't have to break down the still every time you need a drink.

Five years ago, David Smith wore an expensive suit to work every day. "I was a clothes addict(有瘾的人)," he jokes. "I used to carry a fresh suit to work with me, so I could change if my clothes got wrinkled(有褶皱的)." Today David wears casual clothes (便装) to the office. He hardly ever wears a necktie. "I am working harder than ever." David says, "and I need to feel comfortable."

More and more companies are allowing their office workers to wear casual clothes to work. In the United States, the change from formal to casual office wear has been gradual. In the early 1990s, many companies allowed their employees to wear casual clothes on Friday. This became known as "casual Friday". "What started out as an extra one-day-a-week benefit for employees has really become an everyday thing." said business consultant Maisly Jones.

Why have so many companies started allowing their employees to wear casual clothes? "One reason is that it's easier for a company to attract new employees if it has a casual dress code." "A lot of young people don't want to dress up for work," says Owen Black, the owner of a software company, "so it's hard to hire people if you have a conservative (保守的) dress code." Another reason is that people seem happier and more productive when they are wearing comfortable clothes. In a study conducted by Levi Company, 85 percent of employers said that they believe that casual dress improves employee morale (心境, 士气). Only 4 percent of employers said that casual dress has a negative influence on productivity. Supporters of casual office wear also argue that a casual dress code helps them save money. "Suits are expensive, if you have to wear one every day," one person said. "For the same amount of money, you can buy a lot more casual clothes."

    Welcome to your future life!

    You get up in the morning and look into the mirror. Your face is firm and young-looking. In 2035, medical technology is better than ever. Many people your age could live to be 150, so at 40, you're not old at all. And your parents just had an anti-aging(抗衰老的) treatment. Now, all three of look the same age!

    You say to your shirt, “Turn red.” It changes from blue to red. In 2035, “smart clothes” contain particles(粒子) much smaller than the cells in your body. The particles can be programmed to change clothes' color or pattern.

    You walk into the kitchen. You pick up the milk, but a voice says,“ You shouldn't drink that!” Your fridge has read the chip (芯片) that contains information about the milk , and it knows the milk is old . In 2035, every article of food in the grocery store has such a chip.

    It's time to go to work. In 2035, cars drive themselves. Just tell your “smart car” where to go. On the way, you can call a friend using your jacket sleeve. Such “smart technology” is all around you.

    So will all these things come true? “For new technology to succeed,” says scientist Andrew Zolli ,”it has to be so much better that it replaces what we have already.” The Internet is one example—what will be the next?

    When I was a child, my grandmother Adele took me to museums, restaurants, dances. She showered me gifts from her travels around the world. But I can only remember a book she gave me—one book that, to this day, I have not read. She presented me with her own favorite childhood book: Hans Brinker. My grandmother was happy to share this book with me. She even decorated the title page with her proud writing.

    I tried to read it. I adored reading, and would dive into a new pile of books from the library all at once. But something about Hans Brinker just wouldn't let me in. The story was set in Holland, a long time ago. It felt dull and unfamiliar, even though I was a fan of classics of other times and places. I simply read the first pages over and over. I could not progress.

    Standing on a bookshelf in our living room, the book was like something I avoided. It scolded me for not being interested, for not trying hard enough, for disappointing my grandmother. The book started to fit in, almost forgotten, until Adele asked. Had I read it? Did I like it? Always determined, she wanted to know the answer. I would make some kind of excuse, but feel bad, and open it again, hoping for a new reaction. The book weighed on me.

    Years passed and finally Adele and I both accepted that I would never read Hans Brinker. Eventually I cleared the book from the shelf. The Hans Brinker experience led me to set a rule that I've lived by ever since: Do not ask about a book given as a gift and don't let anything become your barrier. What Adele originally wanted to do is to give book-giving special meaning, but she increased the possibility of the owner to be a disappointment.

    Wilbur and Orville Wright were the two youngest sons of Bishop Milton Wright, Wilbur was born on a farm near Millville and Orville was born in August in the house the family would come to occupy for more than 40 years in Dayton.

    Orville would discover in later years that he and Wilbur's first interests in flight began when they were children, with powered rubber-band-helicopter toys that their father would bring home for them from trips around the country. Orville and Wilbur would build duplicates（复制品）of these toys and bounce them off the ceiling. They were just crazy about these things for the reasons that they did not yet understand.

    Both boys loved to solve problems that seemed difficult to others. The more difficult the problem was, the more they saw it as a challenge. Exploring the unknown was such a joy for then that Orville once said, "I can remember when Wilbur and I could hardly wait for the morning to come to get at something that interested us. That's happiness."

    Putting their gift to work, the boys entered the printing business soon after high school. Orville designed and then built a printing press（印刷机）for this enterprise. At first, they did contract printing for other people, and soon one of their customers during the early 1890s was Father Milton's church. They also tried the newspaper business, and although their two newspapers, the West Side News and The Evening Item were considered to be of high quality, Dayton already had daily newspapers, so the Wrights soon returned to contract printing.

    Branching out into other areas, they also opened a bicycle business. Bicycling was the fastest growing sport in the country at that time, and their repair shop soon led them into building bicycles of their own design, often with tools of their own construction, such as the lathe（车床）driven by a one-cylinder gasoline engine built by Orville. The bicycle shop would provide the livelihood（生计）that would allow them to carry out their experiments on airplanes.

    Laughter is a kind of universal body language that is shared by people of all nationalities, skin colors, cultures and traditions. But did you know that the ability to tell real laughter apart from fake (假的) laughter also varies among cultures?

    Greg Bryant, a professor of communication at the University of California, published a study in late July. In the study, 884 people from 21 countries were asked to listen to random recordings of laughter. Some of the recordings were made up of laughs from the bottom of the heart, while others were made by people who were asked to laugh on command.

    The study showed that people around the world have the ability to pick out real laughter, although their abilities vary from country to country. Residents of the Samoan Islands, were particularly good at it, correctly identifying real laughter 56 percent of the time. According to Bryant, people from smaller, less industrialized nations “are more accurate in identifying a natural smile” because they rely heavily on emotional engagement in order to predict others' behavior and create stronger social relationships.

    But how do people from different cultures detect natural laughter so easily? And what characters does real laughter have? As Professor Jessica Wolf of the University of California told the Association for Psychological Science, in real laughter, we produce qualities, such as higher pitch (音调) and volume, as well as faster bursts of no clear sounds.

    By contrast, fake laughter will "sound like speech". According to Science Daily, fake laughter is controlled by the same brain system that controls the lips and tongue. Bryant further explained that this system has active ability, saying "with this speech system, you can make a lot of different noises, including crying, laughter or scream. That's where fake laughter comes from".

    So that? s something to think about: next time one of your friends laughs at something you say, will you be able to tell if it's real or fake?