One of the main challenges facing many countries is how to maintain their identity in the face of globalization and the growing multi-language trend. "One of the main reasons for economic failure in many African countries is the fact that, with a few important exceptions, mother-tongue education is not practiced in any of the independent African states." said Neville Alexander, Director of the Project for the Study of Alternative Education in South Africa at the University of Cape Town.

    In response to the spread of English and the increased multi-language trends arising from immigration, many countries have introduced language laws in the last decade. In some, the use of languages other than the national language is banned in public spaces such as advertising posters. One of the first such legal provisions(规定) was the 1994 "Toubon law" in France, and the idea has been copied in many countries since then. Such efforts to govern language use are often considered as futile by language experts, who are well aware of the difficulty in controlling fashions in speech and know from research that language switching among bilinguals is a natural process.

    It is especially difficult for native speakers of English to understand the desire to maintain the "purity" of a language by law. Since the time of Shakespeare, English has continually absorbed foreign words into its own language. English is one of the most mixed and rapidly changing languages in the world, but that has not been a barrier to acquiring superiority and power. Another reason for the failure of many native English speakers to understand the role of the state regulation is that it has never been the Anglo-Saxon way of doing things. English has never had a state-controlled authority for the language, similar, for example, to the Academic Francaise in France.

    The need to protect national languages is, for most western Europeans, a recent phenomenon—especially the need to ensure that English does not unnecessarily take over too many fields. Public communication, education and new ways of communication promoted by technology, may be key fields to defend.

    Someone has put forward a dream home which is so advanced that its kitchen can suggest what to make with certain things. Also, a Microsoft home doesn't just warn you when you're out of milk—it can send you a fresh gallon.

    But are these innovations just magic, or are they really coming soon to a neighborhood near you? To find out, US News asked some experts to get their opinions about the home of the not-so-distant future. Here's a look at the innovations.

    The housing boom was marked by mass-produced buildings filled with units which look the same. The coming years, however, will give way to a personalized approach to home construction, with houses as more of an instrument of self-expression. "The successful builders will be the ones that figure out how to change their production model enough to make the buyers feel like they are really getting something that is designed for them, not just a model," says Kermit Baker, the chief economist at the American Institute of Architects.

    Future homes will probably shrink. "We will be building smaller but smarter houses," says Ed McMahon, a senior resident fellow at the Urban Land Institute. "Instead of having a room for just one use, consumers will demand homes that make better use of space," says Susanka, whose best-selling book, The Not So Big House, has become increasingly influential in home design. Seldom-used quarters, such as dining and living rooms, will be replaced with space that can serve both functions. "The goal of his 'right-size' home is to fit its owners like a specially cut suit rather than a jacket you buy in a store," says Susanka.

    A bite from a tsetse fly (采采蝇) is an extremely unpleasant experience. It is not like a mosquito, which can put its thin mouthpart directly into your blood, often without you noticing. In contrast, the tsetse fly's mouth has tiny saws on it that saw into your skin on its way to suck out your blood.

    To make matters worse, several species of tsetse fly can transmit diseases. One of the most dangerous is a parasite that causes ＂sleeping sickness＂, or ＂human African trypanosomiasis＂to give it its official name. Without treatment, an infection is usually fatal.

    Like so many tropical diseases, sleeping sickness has often been neglected by medical researchers. However, researchers have long endeavored to understand how it avoids our bodies' defence mechanisms. Some of their insights could now help us eliminate sleeping sickness altogether.

    There are two closely-related single-celled parasites that cause this deathly sleep: Trypanosoma brucei rhodesiense and T. b. gambiense. The latter is far more common: it is responsible for up to 95% of cases, mostly in western Africa. It takes several years to kill a person, while T. brucei rhodesiense can cause death within months. There are still other forms that infect livestock.

    After the initial bite, sleeping sickness symptoms often start with a fever, headaches and aching muscles. As the illness goes on, those infected become increasingly tired, which is where it gets its name. Personality changes, severe confusion and poor coordination can also happen.

    While medication does help, some treatments are toxic and can themselves be deadly, especially if they are given after the disease has reached the brain.

    It is worth noting that sleeping sickness is no longer as deadly as it once was. In the early 20th Century several hundred thousand people were infected each year. By the 1960s the disease was considered ＂under control＂ and had reached very low numbers, making its spread more difficult. But in the 1970s there was another major epidemic, which took 20 years to control.

    Since then, better screening programmes and earlier interventions have reduced the number of cases dramatically. In 2009 there were fewer than 10,000 cases for the first time since records began, and in 2015 this figure dropped to fewer than 3,000, according to the latest figures from the World Health Organisation. The WHO hopes the disease will be completely eliminated by 2020.

    While this decline looks positive, there may be many more cases that go unreported in rural Africa. To eliminate the disease completely, infections have to be closely monitored.

    More problematically, a series of new studies have shown that the parasite is more complicated than previously believed.

    Sleeping sickness has always been considered —— and diagnosed —— as a blood disease, because T. brucei parasites can readily be detected in the blood of its victims.

    Anyone watching the autumn sky knows that migrating birds fly in a V formation, but scientists have long debated why. A new study finds that these big－winged birds carefully position their wingtips and flap(拍动) at the same rate, probably to catch the upward movement of air and save energy during flight.

    There are two reasons birds might fly in a V formation: It may make flight easier, or they're simply following the leader. Squadrons(中 队) of planes can save fuel by flying in a V formation, and many scientists suspect that migrating birds do the same. Models that treated flapping birds like fixed－wing airplanes show that they probably save energy by drafting off each other, but currents created by airplanes are far more stable than those coming off of birds.

    Just as aerodynamic(气动力) calculations would predict, the birds positioned themselves to fly just behind and to the side of the bird in front, timing their wing flaps to catch the uplifting eddies(涡流). When a bird flew directly behind another, the timing of the flapping reversed(相反) so that it could minimize the effects of the downdraft coming off the back of the bird's body. “We didn't think this was possible,” Usherwood says, considering that the difficult achievement requires careful flight and incredible awareness of one's neighbors. “Perhaps these big V formation birds can be thought of quite like an airplane with wings that go up and down.”

    The findings likely apply to other long－winged birds, such as pelicans and geese, Usherwood says. Smaller birds create more complex wakes(尾波) that would make drafting too difficult. The researchers did not attempt to calculate the birds' energy savings because the necessary physiological measurements would be too invasive for an endangered species. Previous studies show that birds can use 20% to 30% less energy while flying in a V.

    Scientists do not know how the birds find that aerodynamic sweet spot, but they suspect that the animals line themselves up either by sight or by sensing air currents through their feathers. In future studies, the researchers will switch to more common birds, such as pigeons or geese. They plan to investigate how the animals decide who sets the course and the pace, and whether a mistake made by the leader can ripple through the rest of the flock to cause traffic jams.

    I'd like to share a little story with you about something that happened when I was four. I remember it clearly. Our loving family dog was nearing the end of his life. My father picked him up and put him in a little bed we had made for him. Our dog, my companion, whom we had cared for, bit my father when he attempted to help him. How could he? Why? I couldn't understand it. I didn't like him anymore.

    I hadn't thought about that story for a long time but something that happened last week brought it back to me. I went to speak with a friend. When I knocked on the door, I met in an instant an angry look and a few harsh(尖刻的)words. When the door was slammed(砰地关上)in my face, I stood there shocked, and in a rush, I was reminded of my dog bit my father 20 years ago or so. What brought that story back was that same feeling of betrayal.

    Both stories taught me something the next day. You see, when I got up in the morning and was told my dog had died, it became clear to me that he must have been in great pain. For him to have bitten a family member, he could not have been himself. Much the same for the other story when I learned that my friend's wife had just left him.

    We are all beings of our environments, our opinions and feelings. And all of those things can cause you to say and do things that can't be understood by those who are not in the same situation with you.

    If you meet someone either behaving out of character or acting in a way that doesn't seem to fit the situation, put out your hand and be patient when you think it is least possible for him to do so. You may turn around a story that has a sad ending simply by your actions.

Adults usually do not remember most of the things that are taught by their teachers at school. But this story is one such lesson that I will never forget. Every time I drift off course, I think of this story.

It was a normal Monday morning, and my teacher was teaching us on important things in life and about devoting ourselves to what is important to us. This is how the story went

An old man lived in a certain part of London, and he would wake up every morning and go to the subway. He would get onto the train right to Central London, and then sit at the street corner and beg. He would do this every single day of his life. He sat at the same street corner and begged for almost 20 years.

His house was dirty, and a stench(恶臭) came out of the house and it smelled terrible. The neighbors could not stand the smell any more, so they called for the police officers to clear the place. The officers knocked down the door and cleaned the house. There were small bags of money all over the house that he had collected over the years.

The police counted the money, and they soon realized that the old man was a millionaire (百万富翁). They waited outside his house expecting to share the good news with him. When the old man arrived home that evening, one of the officers told him that there was no need for him to beg any more as he was a rich man now, a millionaire.

But the old man said nothing at all; he went into his house and locked the door. The next morning he woke up as usual, went to the subway, sat at the street corner and continued to beg.

Clearly, this old man had no great plans, dreams or anything significant for his life. We learn nothing from this story other than staying focused on the things we enjoy doing.