It's 10:00 on a beautiful Sunday morning in California. To my left is some of the most beautiful coastline. I'm walking along a road ordinarily packed with cars on days like this, but today, thanks in part to my $135 entry fee, it is closed to traffic.

    There's only one problem: I should be running, not walking. Over the past year, I've spent hundreds of dollars on running gear(设备) and race entry fees. I've jogged than 1,600 miles training for this event.

    Dozens of runners pass me on either side, each of them experiencing varying degrees of sadness similar to my own. Most of them, like me, have traveled hundreds of thousands of miles to get here, spending $500, $1,000 or more to participate in this event.

    Actually I'm by no means a competitive athlete. My best finish ever was fourth place, in a 5-kftometer race with only 74 participants, many of whom were walking the entire course.

    Last year, over 500,000 runners completed a marathon in the U.S. alone. Nearly all of these runners had absolutely no chance of victory. The PR-personal record-is everyone's definition of a “good race,” whether he finishes in first or 301st.

    I should buy a new watch that not only tracks my location by GPS, but also by counting steps. This can more accurate and much more expensive. Finally, I have reached the finish line. I know that the official race photographers will be taking photos as I cross the line, so I raise my arms in “victory” I finish, in a time of 3:37:55, good for 354th place.

    A few days after the race, the race organizers email me a link to a site where I can preview my official photos 一 and download them, for a fee, of course.

    I wish I could say the feeling was unique; it's probably not Indeed probably a feeling most runners get in most marathons. Running a lot of marathons 9 in fact, may not even be good for your health.

    In America, marathoning is a rich person's sport.

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    Language learning begins with listening. Children are greatly different in the amount of listening they do before they start speaking, and later starters are often long listeners. Most children will “obey” spoken instructions some time before they can speak, though the word “obey” is hardly accurate as a description of the eager and delighted cooperation usually shown by the child. Before they can speak, many children will also ask questions by gesture and by making questioning noises.

    Any attempt to study the development from the noises babies make to their first spoken words leads to considerable difficulties. It is agreed that they enjoy making noises, and that during the first few months one or two noises sort themselves as particularly expressive as delight, pain, friendliness, and so on. But since these can't be said to show the baby's intention to communicate, they can hardly be regarded as early forms of language. It is agreed, too, that from about three months they play with sounds for enjoyment, and that by six months they are able to add new words to their store. This self-imitation leads on to deliberate imitation of sounds made or words spoken to them by other people. The problem then arises as to the point at which one can say that these imitations can be considered as speech.

    It is a problem we need to get our teeth into. The meaning of a word depends on what a particular person means by it in a particular situation and it is clear that what a child means by a word will change as he gains more experience of the world. Thus the use at seven months of “mama” as a greeting for his mother cannot be dismissed as a meaningless sound simply because he also uses it at other times for his father, his dog, or anything else he likes. Playful and meaningless imitation of what other people say continues after the child has begun to speak for himself. I doubt, however, whether anything is gained when parents take advantage of this ability in an attempt to teach new sounds.

    Culture can affect not just language and customs, but also how people experience the world on surprisingly basic levels.

    Researchers, with the help of brain scans, have a shocking differences in perception (感知) between Westerners and Asians, what they see when they look at a city street, for example, or even how they perceive a simple line in a square, according to findings published in a leading science journal.

    In Western countries, culture makes people think of themselves as highly independent individuals. When looking at scenes, Westerners tend to focus more on central objects than on their surroundings. East Asian cultures, however, emphasize inter-dependence. When Easterners look at a scene, they tend to focus on the surroundings as well as the object.

    Using an experiment involving two tasks, Dr. Hedden asked subjects to look at a line simply to estimate its length, a task that played to American's strengths. In another, they estimated the line's length relative to the size of a square, an easier task for the Asians.

    The level of brain activity, by tracking blood flow, was then measured by Brain Scanners. The experiment found that although there was no difference in performance, and the tasks were very easy, the levels of activity in the subjects' brain were different. For the Americans, areas linked to attention were more, when they worked on the task they tended to find more difficult — estimating the line's size relative to the square. For the Asians, the attention areas lit up more during the harder task also—estimating the line's length without comparing it to the square. The findings are a reflection of more than ten years of previous experimental research into East-West differences.

    In one study, for instance researchers offered people a choice among five pens; four red and one green. Easterners were more likely to choose a red pen while Westerners were more likely to choose the green one.

    Culture is not affecting how you see the world, but how you choose to understand and internalize(使内化) it.

    But such habits can be changed. Some psychological studies suggest that when an Easterner goes to the West or vice versa, habits of thought and perception also begin to change. Such research gives us clues to how our brain works and is hopeful for us to develop programs to improve our memory, memory techniques and enhance and accelerate our learning skills.

    Feifei, an 11-year-old boy from Xuzhou, Jiangsu Province, suffered from a sudden acute eye disease which has almost led to blindness. The disease was caused when he overused his eyes during the winter vacation, during which he played computer games for continuous 10 days and nights.

    Many youngsters in China nowadays are increasingly addicted to computer games and other electronic products. This is followed by a series of health problems, with the most typical case being myopia, or nearsightedness.

    According to the latest research report released by the World Health Organization (WHO),the myopia rate among Chinese teenagers ranks first in the world—70 percent of high school and college students. The rate is nearly 40 percent in primary school students, while it is only 10 percent for their peers in the United States.

    There are at least 10 million people in China with severe myopia, and they are likely to get pathological myopia（病理性的近视） in middle age. Pathological myopia can't be treated with glasses or surgery, and it is one of the biggest factors that lead to blindness, Xu Xun, an expert at Shanghai General Hospital, pointed out.

    Experts explain that two major factors lead to the high rate of myopia among Chinese people. One is high academic pressure, and the other one is excessive use of electronic devices over a long period of time. Genetics, on the other hand, are not the main reason, as only 20 percent of Chinese people had myopia in the 1960s.

    "Teenagers are now faced with severe academic pressure, which means they often study without natural light. This increases their risk of becoming nearsighted," Xu said. Experts suggest that youngsters maintain a proper balance between study and rest so as to protect their eyesight, and parents should play an active role in the process.

    Who is smarter? A human being or artificial intelligence?

The question swept the world last week when a Google-developed program called AlphaGo defeated the world top player, South Korean Lee Se-dol, 4-1.

    So, what comes next?

    Some people have been arguing that artificial intelligence, or AI in short, will be a bad thing for humans. In an interview with the BBC in 2014, UK scientist Stephen Hawking warned that “The development of full artificial intelligence could mean the end of the human race.”

    So are we really about to live in the world shown in the Terminator movies?

    “Not quite,” answered The Economist. After all, it's not hard to get a computer program to remember and produce facts. What is hard is getting computers to use their knowledge in everyday situations.

    “We think that, for the human being, things like sight and balance(视觉平衡), are natural and ordinary in our life.” Thomas Edison, founder of Motion Figures, a company that is bringing AI to boys, told the newspaper. “But for a robot, to walk up and down just like human beings requires various decisions to be made every second, and it's really difficult to do.”

    As The Economist put it, “We have a long way to go before AI can truly begin to be similar to the human brain, even though the technology can be great.”

    Meanwhile, John Mark off of The New York Times said that researchers should build artificial intelligence to make people more effective.

    “Our fate is in our own hands,” he wrote. “Since technology depends on the values of its creators, we can make human choices that use technology to improve the world.”