Not so long ago, most people didn't know who Shelly Ann FrancisPryce was going to become. She was just an average high school athlete. There was every indication that she was just another American teenager without much of a future. However, one person wants to change this. Stephen Francis observed then eighteen-year-old Shelly Ann as a track meet and was convinced that he had seen the beginnings of true greatness. Her time were not exactly impressive, but even so, he sensed there was something trying to get out, something the other coaches had overlooked when they had assessed her and found her lacking. He decided to offer Shelly Ann a place in his very strict training sessions. Their cooperation quickly produced results, and a few years later at Jamaica's Olympic trails in early 2008, Shelly-Ann, who at that time only ranked number 70 in the world, beat Jamaica's unchallenged queen of the sprint(短跑).

“Where did she come from?” asked an astonished sprinting world, before concluding that she must be one of those one-hit wonders that spring up from time to time, only to disappear again without signs. But Shelly-Ann was to prove that she was anything but a one-hit wonder. At the Beijing Olympics she swept away any doubts about her ability to perform consistently by becoming the first Jamaican woman ever to win the 100 meters Olympic gold. She did it again one year on at the World Championship in Berlin, becoming world champion with a time of 10.73— the fourth fastest time ever.

Shelly-Ann is a little woman with a big smile. She has a mental toughness that did not come about by chance. Her journey to becoming the fastest woman on earth has been anything but smooth and effortless. She grew up in one of Jamaica's toughest inner-city communities known as Waterhouse, where she lived in a one-room apartment, sleeping four in a bed with her motherand two brothers. Waterhouse, one of the poorest communities in Jamaica, is a really violent and overpopulated place. Several of Shelly-Ann's friends and family were caught up in the killings; one of her cousins was shot dead only a few streets away from where she lived. Sometimes her family didn't have enough to eat. She ran at the school championships barefooted because she couldn't afford shoes. Her mother Maxime, one of a family of fourteen, had been an athlete herself as a young girl but, like so many other girls in Waterhouse, had to stop after she had her first baby. Maxime's early entry into the adult world with its responsibilities gave her the determination to ensure that her kids wouldnot end up in Waterhouse's roundabout of poverty. One of the first things Maxime used to do with Shelly-Ann was taking her to the track, and she was ready to sacrifice everything.

        It didn't take long for Shelly-Ann to realize that sports could be her way out of Waterhouse. On a summer evening in Beijing in2008, all those long, hard hours of work and commitment finally bore fruit. The barefoot kid who just a few years previously had been living in poverty, surrounded by criminals and violence, had written a new chapter in the history of sports.

        But Shelly-Ann's victory was far greater than that. The night she won Olympic gold in Beijing, the routine murders in Waterhouse and the drug wars in the neighbouring streets stopped. The dark cloud above one of the world's toughest criminal neighbourhoods simply disappeared for a few days.“I have so much fire burning for my country,” Shellysaid. She plans to start a foundation for homeless children and wants to build acommunity centre in Waterhouse. She hopes to inspire the Jamaicans to lay down their weapons. She intends to fight to make it a woman's as well as a man's world.

        As Muhammad Ali puts it, “Champions aren't made in gyms. Champions are made from something they have deep inside them. A desire, a dream, a vision.” One of the things Shelly-Ann can be proud of is her understanding of this truth.

    In the mid­1950s，I was a somewhat bored early­ado lescent male student who believed that doing_any_more_than_necessary_was_wasted_effort.One day，this approach threw me into embarrassment.

    In Mrs.Totten's eighth­grade math class at Central Avenue School in Anderson，Indiana，we were learning to add and subtract decimals (小数)．

    Our teacher typically assigned daily homework，which would be recited in class the following day.On most days，our grades were based on our oral answers to homework questions.

    Mrs.Totten usually walked up and down the rows of desks requesting answers from student after student in the order the questions had appeared on our homework sheets.She would start either at the front or the back of the classroom and work toward the other end.

    Since I was seated near the middle of about 35 students，it was easy to figure out which questions I might have to answer.This particular time，I had completed my usual two or three problems according to my calculations.

What I failed to expect was that several students were absent，which threw off my estimate.As Mrs.Totten made her way from the beginning of the class，I desperately tried to determine which math problem I would get.I tried to work it out before she got to me，but I had brain freeze and couldn't function.

    When Mrs.Totten reached my desk，she asked what answer I'd got for problem No.14.“I...I didn't get anything，”I answered，and my face felt warm.

     “Correct，”she said.

    It turned out that the correct answer was zero.

    What did I learn that day？First，always do all your homework.Second，in real life it isn't always what you say but how you say it that matters.Third，I would never make it as a mathematician.

    If I could choose one school day that taught me the most，it would be that one.

    Tonight, my piano concert was the most important thing in my family. My grandparents were coming by plane to hear me play. Even my busy Aunt Dianne who is on TV every night reading the news, was coming.

    But one thing was for sure. I would never win an award for my piano playing. And that's just because the more I practiced ,the more nervous I got. So there I was, on stage, in my beautiful dress, and I sat down at the piano. But when I started to play, I hit a wrong note. I told myself to start over. But then I hit the wrong note again. It was as if I hadn't practiced at all.

    Finally the disaster was over. I ran off the stage. I couldn't understand why people were applauding. But they were. My mom and my dad had flowers for me, and we were all supposed to go out for a nice dinner, but I couldn't. I just wanted to go home and cry and never go anywhere again. After we went back home, Aunt Dianne just came in and sat down on the side of my bed.

    "It was my first night on the air," she said."I had never been on television before, and I made a mistake. I mispronounced my name and the name of the news show. And you know what? No one even noticed but me. Just like tonight, no one noticed—just you". Aunt Dianne was right. I think we are harder on ourselves than anyone else is. Maybe I will leave my room. And maybe, I'll play the piano again.

    Do you think horseback riding is easy? Well, you are wrong. Horseback riding is one of the most challenging sports in the world today.

    As you know, a horse has the instinct to run away when afraid. When he becomes puzzled, he becomes afraid. When your silent communication is confusing, he does not ask you to repeat what you have said. Instead, he runs forward, he jumps to the side, he kicks out, or he freezes in place. Most of the time, however, you won't know your communication is confusing until it is too late. When he runs forward, you will fall back. When he jumps to side, you will fall the other way. When he kicks out or freezes in place, you will fly over his head.

    If you want to be good at horseback riding, you must practice. Being ridden does not come naturally to horses. They have to be trained. For example, to ask them to go forward, you usually tap them with your heels. But, if you get on untrained horses, they won't know that a tap means go. Instead, they will most likely run around like a wild animal out of fear.

    Contrary to popular belief, horseback riding does take skill. If you believe horseback riding doesn't take skill, you most likely have only ridden at a farm that provides a well-trained horse. To me, that is not actual riding. And although it may seem easy to you, you were not the person to teach that horse that a saddle is not frightening. You were not the person to fall off that same horse at the beginning of his training. When horses are first taught to be ridden, all they do is run, kick out, and rear, which is the act of standing on their back legs only.

    Warford is an optometrist (验光师) in Florida. He has seen an increase in "computer vision syndrome (电脑视力综合症)"in children. "A lot more children come into the office either because their parents have noticed that they have headaches or red or watery eyes or discomfort, or because their nearsightedness appears to be increasing and they're worried," he says.

    Dr. Watford says part of the problem is that children may be more likely to pay no attention to early warning signs than adults. "Even if their eyes start to feel uncomfortable or they start to get a headache, they're less likely to tell their parents, because they don't want to have the game or whatever taken away," he explains.

    He says another part of the problem is that people blink (眨眼) less often when they use digital devices. He says, "A person who uses an electronic device blinks about one third as much as we normally do in everyday life. And that can result in the front part of the eye drying and not staying protected like normal."

    Eye doctors offer suggestions like the 20 /20 /20 rule. That means every twenty minutes look away twenty feet or more for at least twenty seconds from whatever device you're using.

    Other suggestions include using good lighting and spending less time looking at screens. Many experts say children should spend no more than two hours a day using digital devices—with no screen time for children under two.

    But not all eye doctors have noticed an increase in problems in children. Dr. David Hunter, for instance, says, "While it is possible to develop fatigue looking at screens for a long time, there's certainly no proof that it actually causes any damage to the eyes."

    Have you ever spent an afternoon in the backyard, maybe grilling or enjoying a basketball game, when suddenly you notice that everything goes quiet? There is an old phrase "calm before the storm", often used in a situation—a quiet period just before a great activity or excitement. According to our own experience, we know there is actually calm before the storm. But what causes this calm? And is it always calm before the storm? Let's hear what scientists have to say.

    A period of calm happens in a particular kind of storm, the simplest kind of storm—a single-cell thunderstorm. In this type of thunderstorm, there is usually only one main updraft, which is warm, damp air and drawn from places near the ground. Storms need warm and damp air as fuel, so they typically draw that air in from surrounding environment. Storms can draw in the air that fit their need from all directions—even from the direction in which the storm is traveling.

    As the warm, damp air is pulled into a storm system, it leaves a low-pressure vacuum (真空) coming after. The rising air meets the cold dry air that has already existed in the storm clouds, thus the temperature of the warm, damp air drops, and the water vapour (水蒸汽) in it changes into tiny drops that are a precondition of rain. These drops accumulate and build on larger particles like dust, until they grow large enough to form raindrops.

    This warm, damp air keeps moving upwards, but it becomes cooler and drier during its trip through cloud. When it reaches the top of the cloud, the air gets spit out (被挤出) at the top. This air is sent rolling out over the big thunderclouds. From there, the air goes down. Warm and dry air is relatively stable, and once it covers a region, that air, in turn, causes the calm before a storm.

    Most thunderstorms, though, don't start with calm. That's because most are actually groups of storms with complex wind patterns. There's so much air moving up and down storm groups that the calm before the storm never happens. Instead, before the storm,让 might be really windy!