About 70 scientists were working on a very busy project. All of them felt really desperate due to the pressure of work and the demands of their boss but everyone was loyal to him and did not think of quitting their job.

    One day, one scientist came to his boss and told him, “Sir, I've promised to take my children to the exhibition going on in our township so I want to leave at 5:30 p. m.” His boss replied, “OK. You're permitted to leave the office early today.”

    The scientist started working. He continued his work after lunch. As usual, he got involved to such an extent that he looked at his watch only when he felt he was close to completion. The time was 8:30 p. m. suddenly he remembered his promise to the children. He looked for his boss but he was not there. Having told him in the morning himself, he closed everything and left for home. Deep within himself, he was feeling guilty for having disappointed his children. He reached home. The children were not there. His wife alone was sitting in the hall and reading magazines. The situation was explosive; any talk would boomerang on him. His wife asked him, “Would you like to have coffee or shall I straight away serve dinner if you are hungry?” The man replied, “If you would like to have coffee, I too will have but what about the children?” His wife replied, “You don't know? Your boss came here at 5:15 p. m. and has taken them to the exhibition.”

    What had really happened was the boss who gave him permission was observing him working seriously at 5:00 p. m. He thought to himself: this person will not leave the work, but he's promised to take his children to the exhibition. So he took the lead in taking them there. The boss does not have to do it every time. But once it's done, loyalty is established.

    That is why all the scientists at Thumba continued to work under their boss even though the stress was extraordinarily huge. By the way, can you boldly guess who the boss was? He was none other than the mastermind behind India's successful nuclear weapons program, Dr. APJ Abdul Kalam, former president of India.

    While Jennifer was at home taking an online exam for her business law class, a monitor（监控器）a few hundred miles away was watching her every move.

    Using a web camera equipped in Jennifer's Los Angeles apartment, the monitor in Phoenix tracked how frequently her eyes moved from the computer screen and listened for the secret sounds of a possible helper in the room. Her Internet access was locked — remotely — to prevent Internet searches, and her typing style was analyzed to make sure she was who she said she was: Did she enter her student number at the same speed as she had in the past? Or was she slowing down?

    In the battle against cheating, this is the cutting edge and a key to encouraging honesty in the booming field of online education. The technology gives trust to the entire system, to the institution and to online education in general. Only with solid measures against cheating, experts say, can Internet universities show that their exams and diplomas are valid — that students haven't just searched the Internet to get the right answers.

    Although online classes have existed for more than a decade, the concern over cheating has become sharper in the last year with the growth of “open online courses”. Private colleges, public universities and corporations are jumping into the online education field, spending millions of dollars to attract potential students, while also taking steps to help guarantee honesty at a distance.

    Aside from the web cameras, a number of other high-tech methods are becoming increasingly popular. Among them are programs that check students' identities using personal information, such as the telephone number they once used.

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    About 5,000 children die each day due to preventable diseases such as cholera and dysentery (痢疾) , which spread when people use unclean water for drinking or cooking. A lack of water for personal health leads to the spread of totally preventable diseases like trachoma, which has blinded some six million people.

    Water troubles also trap many low-income families in a cycle of poverty and poor education and the poorest suffer most from lack of access to water. People who spend much of their time on ill health, caring for sick children, or collecting water at distances averaging 3.75 miles a day don't have educational and economic opportunities to better their lives.

    Agriculture is called the lion's share of freshwater worldwide, using some 70 percent, and industrial uses consume another 22 percent. Water areas have no political borders and nations don't always work together to share common resources, so water can be a frequent source of international conflict as well.

    Day-by-day demand keeps growing, further needing water sources, from great rivers to groundwater. “We're going deeper into debt on our groundwater use,” Postel said, “and that has very significant impacts on global water security. The rate of groundwater consumption has doubled since 1960.”

    Some of Earth's groundwater is fossil water created when Earth's climate was far different. Today such water is as limited as petrol. “But we're pumping much of them out faster than ever,” Postel explained. “Humanity's growing thirst also causes a major problem about water and our ecosystems. And that also creates a cost to us, to our sons and to our grandsons, not just to nature.”

Everyone has got two personalities—the one that is shown to the world and the other that is secret and real. You don't show your secret personality when you're awake because you can control yourself, but when you're asleep, your sleeping position shows the real you. In a normal night, of course, you often change your sleeping positions. The important position that best shows your secret personality is the one that you fall asleep with.

    If you go to sleep on your back, you're a very open person. You normally trust people and you are easily influenced by fashion or new ideas. You don't like to upset people. So you never express your real feelings. You're quite shy and you aren't very confident.

    If you sleep on your stomach, you are a person who likes to keep secrets. You worry a lot and you're always easily becoming sad. You never want to change your ideas, but you are satisfied with your life the way it is. You usually live for today not tomorrow.

    If you sleep curled up(卷曲), you are probably a very nervous person. You have a low opinion of yourself and you often protecting yourself from being hurt, so you are very defensive. You're shy and you don't usually like meeting people. You prefer to be on your own. You're easily hurt.

    If you sleep on your side, you have usually got a well-balanced(平衡的) personality. You know your strengths and weaknesses. You're usually careful. You believe in yourself. You sometimes feel anxious, but you don't often get unhappy. You always say what you think, even if it makes people rather angry.

    While faking and fierce looks are among animals great defenses, many species know that everyone runs from a big stink (臭气) too.

    Vulture (秃鸳)

    Vultures, are street sweepers that feast on the rotting flesh of dead animals, which benefits us by ridding our highways and landscapes of animal bodies and the bacteria they might carry. When vultures feel threatened they vomit, and the smell of vomited-on dead bodies puts of most predators. Throwing up allows the vulture to fly away more quickly-and the vomit can hurt the aggressor's eyes and face.

    Opossum (负鼠)

    In some ways opossums have it easy. In order to become "dead", they don't have to fax anyone a death certificate. They just lie there with their tongues hanging out with the smell of dead flesh, sometimes for hours, effectively convincing potential predators they can find a much fresher meal elsewhere. Even if they keep getting attacked, they won't move any more than a human statue until the threat has passed.

    Hoatzin (磨雉)

    Hold your nose and meet the hoatzin, a bird of distinctions, not the least of which is that it smells like fresh cow shit. The animal mostly eats leaves and it's the only bird known to digest by fermentation, like a cow. This process is what causes its smell and has earned it the nickname the "stink bird

    Millipedes (千足虫)

    Millipedes are tricky. For starters they look wormy. Their name is deceptive, too: Their legs number about 750. Their major defense is to curl up into a ball. They, though, also release a harm eyes, and leave a horrible smell on their attackers.

    Sea Hare (海兔)

    The graceful sea hare is plain in taste in the first place, so it's not the most popular dish in the seafood chain. Nonetheless this type of sea creature has a pretty creative smell-related defense that is almost the opposite of its smelly companions on this list. The sea hare gives out a slimy, purple ink, the substance which makes food less palatable to predators.

    Researchers using lobsters (2-f) as model predators found that the sea blocks the lobsters receptive mechanism. In other words, the sea hare gives its attacker the equivalent of a stuffy nose so they don't know how appealing it is.

    Most people know something about the greenhouse effect. Factories send gasses such as carbon dioxide, or CO₂, into the atmosphere, the air around the earth. In the past, this wasn't a problem because trees absorbed the CO₂. But now people in many countries are cutting down billions of trees all around the world. At the same time, factories are sending more CO₂ into the atmosphere. It's difficult to believe, but factories put billions of tons of CO₂ into the atmosphere every year. One ton is over 2000 pounds, so it is a lot of pollution. There is too much CO₂ and there aren't enough trees, so the world is getting warmer. In other words, we have a greenhouse effect. This is terrible for the environment.

    What can we do about this? Firsts we can stop using so much coal and oil. We can learn to use different kinds of energy: the sun, wind, steam from volcanoes, and heat from inside the earth. Second, instead of cutting down trees, we should plant more trees. One tree can absorb ten pounds of carbon dioxide every year.

    The trees are good for the earth's atmosphere and for Guatemala (拉丁美洲国家危地马拉).In small towns and villages in Guatemala, most women are poor and have hard lives. Trees help them in three ways. First, the Connecticut factories pay them to plant the trees. Their pay is com, not money. The com is good for their children. Second, these women know a lot about their environment. They know where to plant when to plant, and what kinds of trees to plant. For example, they plant many fruit trees. The fruit gives them vitamins for their families^' diets. Other trees are good for firewood. In a few years, the women won't spend so much time looking for firewood. Third, all these trees are good for the soil. Now rain can't wash the soil down from the mountains so easily.

    This plan isn't enough to stop the greenhouse effect. However, it's a start. The woman of Guatemala are helping themselves and helping their environment.