Recordings of angry bees are enough to send big, tough African elephants running away, a new study says. Beehives (蜂窝)—either recorded or real—may even prevent elephants from damaging farmer's crops.

    In 2002, scientist Lucy King and her team found that elephants avoid certain trees with bees living in them. Today, Lucy wants to see if African honeybees might discourage elephants from eating crops. But before she asked farmer to go to the trouble of setting up beehives on their farms, she needed to find out if the bees would scare elephants away.

    Lucy found a wild beehive inside a tree in northern Kenya and set up a recorder. Then she threw a stone into the beehive, which burst into life. Lucy and her assistant hid in their car until the angry bees had calmed down. Next，Lucy searched out elephant families in Samburu National Reserve in northern Kenya and put a speaker in a tree close to each family.

    From a distance, Lucy switched on the pre-recorded sound of angry bees while at the same time recording the elephants with a video camera. Half the elephant groups left the area within ten seconds. Out of a total of 17 groups, only one group ignored the sound of the angry bees. Lucy reported that all the young elephants immediately ran to their mothers to hide under them. When Lucy played the sound of a waterfall (瀑布) instead of the angry bees to many of the same elephant families, the animals were undisturbed. Even after four minutes, most of the groups stayed in one place.

    Lucy is now studying whether the elephants will continue to avoid the sound of angry bees after hearing it several times. She hasn't tested enough groups yet to know, but her initial (最初的) results were promising enough to begin trials with farmers. She has now begun placing speakers in the fields to see if elephants are frightened away.

    When asked about happiness, we usually think of something extraordinary, an absolute delight, which seems to get rarer the older we get.

    For kids, happiness has a magical quality. Their delight at winning a race or getting a new bike is unreserved (毫无掩饰的).

    In the teenage years the concept of happiness changes. Suddenly it's conditional on such things as excitement, love and popularity. I can still recall the excitement of being invited to dance with the most attractive boy at the school party.

    In adulthood the things that bring deep joy—love, marriage, birth—also bring responsibility and the risk of loss. For adults, happiness is complicated.

    My definition of happiness is “the capacity for enjoyment”. The more we can enjoy what we have, the happier we are. It's easy to overlook the pleasure we get from the company of friends, the freedom to live where we please, and even good health.

    I experienced my little moments of pleasure yesterday. First I was overjoyed when I shut the last lunch-box and had the house to myself. Then I spent an uninterrupted morning writing, which I love. When the kids and my husband came home, I enjoyed their noise after the quiet of the day.

    Psychologists tell us that to be happy we need a mix of enjoyable leisure time and satisfying work. I don't think that my grandmother, who raised 14 children, had much of either. She did have a network of close friends and family, and maybe this is what satisfied her.

    We, however, with so many choices and such pressure to succeed in every area, have turned happiness into one more thing we've got to have. We're so self-conscious about our “right” to it that it's making us miserable. So we chase it and equal it with wealth and success, without noticing that the people who have those things aren't necessarily happier.

    Happiness isn't about what happens to us—it's about how we see what happens to us. It's the skillful way of finding a positive for every negative. It's not wishing for what we don't have, but enjoying what we do possess.

    Global GDP in 2030 will be 14% higher as a result of AI (Artificial Intelligence), thanks to improving labor productivity and increasing consumer demand, says a report.

    The report could increase the enthusiasm of economic policymakers and the public, and show the power of technology in changing not only people's daily lives, but also economic activities. However, history tells us that, while technological advancements have brought us benefits, they have also led to great social disorders, by changing the production and labor structures, and forcing many workers to either adapt to the changes or lose their jobs. In the 18th century, for instance, skilled workers rose up to resist the Industrial Revolution, destroying machinery in the early 19th century. We may not see similar protests today, but history should serve as a warning against the application of AI technology.

    While we may gain a lot of benefits from AI, we must work out plans to reduce its negative effect on society, especially for workers. AI can raise productivity and expand GDP, but it can also make non-adaptive workers jobless. In India, some technology personnel have already felt the negative effect of information technology. As technology industries across the world seek increasing support from automation（自动操作）, robotics and big data analysis, some technology workers have already lost their jobs.

    In their 2013 research study, Michael Osborne and Carl Frey from Oxford University estimated 47% of the jobs in the United States are “at risk” of being automated in the next 20 years. They said jobs in transportation and office and administrative support are at high risk of being automated. And Kaifu Lee recently said that robots could take away about 50% of all jobs from humans in the next decade.

    Those estimates may sound sensational and the impact of technological advancements may not be that serious, as they will also create jobs in new industries. However, policymakers should consider how to better embrace the technological wave to bring benefits while taking action to minimize its negative effects. The government therefore needs to work together with business leaders and social organizations, to promote training programs for potentially helpless workers, in order to make them more capable of adapting to the structural changes in industries and job markets in the future.

Four apps for students to learn English

    Quizlet

    Quizlet is a learning app—a computer program you use on your mobile device. It can help users build and test their knowledge of English words and terms. Quizlet has word sets for millions of subjects. And, it is quickly becoming a useful mobile tool for language learners.

    Socrative

    In Socrative, teachers can create timed learning games. In class, students compete individually or as part of a team against classmates. One game students love is called space Race. In this game, if a team answers a question correctly, their rocket moves forward. This team whose rocket gets to the end first wins. Also, teachers can use Socrative as an “exit ticket, ”a question they can ask students about what they learned in that day's class. Students write their answers on their mobile devices. Then, the teacher can show the answers on a shared video screen.

    QR Codes

    AQRCodeisakindofsignthatasmartphonecanreadwithitscamera. When your phone camera reads a QR code, it takes you to a website, image, video or anything you want to share. For example, one will take you to the VOA Learning English website.

    Evernote

    Evernote lets users store and share notes, images and recordings in one place. Teachers can also use Evernote to give homework.

    Stained glass (彩色玻璃) artists create different designs by making cuts on the glass to “score” it and then breaking off the pattern that they want to use in the finished product. The most difficult cut in stained glass is called an inside cut. Basically, it's a curved (弯曲的) line where you throw away the part inside of the curve. The problem with inside cuts is that the edges of the curve tend to break off when the pieces of scored glass are broken apart.

    As the artist talked about inside cuts, he said, “The glass will break into pieces if you try to cut too much off at once. The best way to do an inside cut is to slice off smaller curves piece-by-piece. In fact, it's not just the best way to do it, but it's the only way to do it.”

    How many times do you try to make a big change and cut the entire piece at once? We convince ourselves that we can do this all the time. We'll commit to transforming our diet overnight or we get inspired to launch a business in a weekend or we finally get motivated to work out and push ourselves to the edge of burning out.

    Why not approach your goals and dreams like a stained glass artist? Starting by slicing a shallow curve and breaking a small piece off, you cut a slightly deeper curve and break that off until you have your full inside cut. By slowly cutting deeper and deeper curves, you prevent the glass from breaking as it changes shape.

    Of course, change isn't easy — no matter how you do it. Slow gains are boring, but if we keep making small improvements, then pretty soon we will end up with a beautiful masterpiece on our hands instead of a bunch of broken pieces.

    My children are perfect. All four of them. Perfect and beautiful and clever. I bet yours are, too. Except, of course, they are not. In reality, my children and yours are likely to be reasonably average in terms of looks, behavior, intelligence and charm. That's why it is called average. Your belief in your child being special is more probably a biological thing than a fact.

    A loved one, particularly a loved child, is edited as we observe them. Other people's children are spoiled; ours are spirited. Theirs are naughty; ours are confident.

    This is all natural and even touching when not taken too far. However, it is one thing feeding this idea to ourselves but feeding it to our children may be a little less desirable. We have the idea that — unlike my parents' generation — we should build our children's self-respect as high as we can. Therefore, their random scribble (胡写乱画) is up there with Picasso, their C-minus is an unfortunate oversight on the part of the teacher, and the fact that no one wants to be friends with them is because they are particularly clever or sensitive.

    Children see through this kind of thing very quickly and ignore their parents' praises as a matter of course. As they grow up, they sense that the wider world judges them differently. This leads to a – hopefully gentle – cynicism (猜忌) about anything their parents tell them about their achievements. Perhaps that is OK — but I'm not sure if it is good for them to have the parental praise so overlooked.

    If parents were a little harsher sometimes, this could have two positive effects — first, when praise came, it would be more likely to be believed and, second, it would fit in rather more accurately with the picture of reality that the child is forming in their heads.

    A lot of pressure is put on children who are told they are beautiful, special and perfect. Because then, where is there to go? Only downwards. They become too much aware of their status in your eyes, and a danger must be that they fear failing you. To be over-praised by your parents is the counter side of being criticized all the time. Both can have negative consequences.

    It is important to give your children the freedom to be flawed (缺点) — to know that it's OK to be imperfect, and that, in fact, we often love people for their flaws — perfect people (whom we can only imagine, as they do not exist) are easy to respect, but hard to love.

    Now I am nearly 60, my main insight is that I am much less special than I once believed. This knowledge has actually been helpful in leading a more well-balanced life.

    I certainly wouldn't like to go back to attitudes that my parents, particularly my father, held, that to praise the child was to "spoil them" or make them bigheaded. However, the history of families is like the history of everything else — the story of overreactions. We praise our children to the skies, partly because we think it makes them feel good, but also because it makes us feel good. And perhaps it is more the latter than the former.

    Too much love can be as big a burden as a shortage of it. My advice is to limit your praise. Then every piece of praise will count, rather than being just ignored.