When the evening is coming, my dear son and I are preparing for the tape time. “Shoes on,” I remind 9-year-old Sam. “Snakes are always waiting for the chance to kiss you. But with our feet stepped into my car, we are safe.” We take blankets and cups of milk and head out to the shelter that serves as our garage. This has become our bedtime habit.

    I press “play.” A motherly voice fills the car. My mother and my aunt send us books on tape obtained from secondhand shops or rescued from the back of drawer. Maybe no one in England lays cassettes anymore, but I still love them.

    Sam rests on his seat. He's sitting in the front seat. I am listening to the cassette. But I am also thinking. In a month's time, my boy will be 10. Next year, he will be 11. And so it will go on, until he leaves me and his father and his sister to live out his own stories— as it is only right and proper he should.

    Will he think back to the times when he sat in the dark in a car in Africa, listening to tales of Wales in World War Ⅱ, the finest lady detective of Botswana, or a country he has visited, and tells me he finds them “very interesting”? Will he think , when he is grown-up, the poor mum always makes the ancient tape player which is out of date work?

    I like to believe that he will recall those wonderful moments. By then, perhaps, my child will realize a deep love of sharing and understanding by listening to the old tape player. I hope Sam will think that these evenings we spend in the car are a story themselves. It is his own first chapter. In time my boy will ease off the hand brake and roll out into the world. Until then, I'll keep pressing “play”.

    It is said that if you want to stay young, sit down and have a good think. This is the research finding of a team of Japanese doctors, who say that most of our brains are not getting enough exercise — and as a result, we are growing old unnecessarily soon.

    Professor Taiju Matsuzawa wanted to find out why otherwise healthy farmers in northern Japan appeared to be losing their ability to think and reason at a relatively early age, and how the process of aging could be slowed down. With a team of colleagues at Tokyo National University, he set about measuring brain volumes of a thousand people of different ages and varying occupations. Computer technology enabled the researchers to obtain precise measurements of the volume of the front and side parts of the brain, which controls functions like eating and breathing, does not contract with age, and one can continue living without intellectual on economical faculties. Contraction of front and side parts — as cells die off — was observed in some subjects in their thirties, but it was still not evident in some sixty-and seventy-year-olds. Matsuzawa concluded from his tests that there is a simple way to the contraction normally connected with age — using the head.

    The findings show in general terms that contraction of the brain begins sooner in people in the country than in the town. Those least at risk, says Matsuzawa, are lawyers, followed by university professors and doctors. White collar workers doing routine work in government offices are, however, as likely to have shrinking (萎缩) brains as the farm worker, bus driver and shop assistant.

    Matsuzawa's findings show that thinking can prevent the brain from shrinking. Blood must circulate properly in the head to supply the fresh oxygen the brain cells need. “The best way to maintain, good blood circulation is through using the brain.” he says. “Think hard and engage in conversation. Don't rely on pocket calculators.”

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    Every person has their own way of saying things, their own special expressions. Many everyday American expression are based on colors.

    Red is a hot colour. Americans often use it to express heat. They may say they are red hot about something unfair. When they are red hot they are very angry about something. The small hot tasting peppers found in many Mexican foods are called red hots for their colour and their fiery taste. Fast loud music is popular with many people. They may say the music is popular with many people. They may say the music is red hot, especially the kind called Dixicland jazz.

    Pink is a lighter kind of red. People sometimes say they're in the pink when they're in good health. The expression was first used in America at the beginning of the 20th century. It probably came from many babies who were born with a nice pink colour showing good health.

Blue is a cool colour. The traditional blues music in t he United States is the opposite of red hot music. Blues is slow, sad and soulful. Duke Ellington and his orchestra recorded a famous song—Mood Indigo—about the deep blue colour, indigo. In the words of the song: “You aren't blue till you've had that Mood Indigo.” Someone who is blue is very sad.

    The colour green is natural for trees and grass. But it is an unnatural colour for humans. A person who has a sick feeling in his stomach may say he feels a little green. A passenger on a boat who is feeling very sick from high waves may look very green.

    Sometimes a person may be upset because he does not have something as nice as his friend's, like a fast new car. That person may say he is green with envy. Some people are green with envy because a friend has more dollars of greenbacks. Dollars are called greenbacks because that is the colour of the back side of the paper money.

    The colour black is often used in expressions. People describe a day in which everything goes wrong as a black day. The date of a major tragedy is remembered as a black day. a blacklist is illegal now. But at one time, some businesses refused to employ people who were on a blacklist for belonging to unpopular organizations.

Hollywood's theory that machines with evil(邪恶) minds will drive armies of killer robots is just silly. The real problem relates to the possibility that artificial intelligence(AI) may become extremely good at achieving something other than what we really want. In 1960 a well-known mathematician Norbert Wiener, who founded the field of cybernetics（控制论）, put it this way: “If we use, to achieve our purposes, a mechanical agency with whose operation we cannot effectively interfere(干预), we had better be quite sure that the purpose put into the machine is the purpose which we really desire.”

A machine with a specific purpose has another quality, one that we usually associate with living things: a wish to preserve its own existence. For the machine, this quality is not in-born, nor is it something introduced by humans; it is a logical consequence of the simple fact that the machine cannot achieve its original purpose if it is dead. So if we send out a robot with the single instruction of fetching coffee, it will have a strong desire to secure success by disabling its own off switch or even killing anyone who might interfere with its task. If we are not careful, then, we could face a kind of global chess match against very determined, super intelligent machines whose objectives conflict with our own, with the real world as the chessboard.

The possibility of entering into and losing such a match should concentrate the minds of computer scientists. Some researchers argue that we can seal the machines inside a kind of firewall, using them to answer difficult questions but never allowing them to affect the real world. Unfortunately, that plan seems unlikely to work: we have yet to invent a firewall that is secure against ordinary humans, let alone super intelligent machines.

Solving the safety problem well enough to move forward in AI seems to be possible but not easy. There are probably decades in which to plan for the arrival of super intelligent machines. But the problem should not be dismissed out of hand, as it has been by some AI researchers. Some argue that humans and machines can coexist as long as they work in teams—yet that is not possible unless machines share the goals of humans. Others say we can just “switch them off” as if super intelligent machines are too stupid to think of that possibility. Still others think that super intelligent AI will never happen. On September 11, 1933, famous physicist Ernest Rutherford stated, with confidence, “Anyone who expects a source of power in the transformation of these atoms is talking moonshine.” However, on September 12, 1933, physicist Leo Szilard invented the neutron-induced(中子诱导) nuclear chain reaction.

    Teens may become more private during adolescence (青春期) because they are learning how to be more independent, says Carl Pickhardt, a Texas­based scientist who studies parenting adolescents. "As they enter adolescence, parents have less control," he says. "You're going to have less communication with the kid who is now entering a larger and more risky world."

    However, Pickhardt says, this does not mean that parents should just sit back and do without any information. He says that parents should tell their kids that there are still things they need to know about, such as why their teen was late getting home from school one day.

    Iowa's mom Patty Link knows this fight well. The mom of three is raising two teenage boys: Graham, a 14-year-old eighth grader, and Carter, a 16-year-old high school student. She says that becoming friends with the parents of her children's friends has helped.

    "A lot of times if I want to get any information out of them, I'll say, 'Oh, I can talk to Adam's mom and she will tell me what was going on Friday night', and it will lead to some other discussion, "she says.

    Parents should watch their use of questions, Pickhardt says, because they can stand for authority (权威), and that is likely to not go over well with teens. "They want their independence to be respected, "he says. Pickhardt suggests using requests such as, "It could really help me if you could tell me," "I would really appreciate it if you let me know, "or "Could you help me better understand." But sometimes teens make mistakes and parents have to correct them. Parents should plainly (直率地) state the problem, Pickhardt says, and avoid judgments of character.

    Parents can also use technology to feel connected. One recent study showed that many teens are friends with their parents on Facebook—and only 5 percent limit what their parents can see.

When you were at school, were you ever told to stop daydreaming and concentrate? It was easy for your mind to wander if you weren't interested in what you were learning or if you had better things to think about. {#blank#}1{#/blank#} But understanding how to do it, and knowing what is distracting you, can help.

Scientists have looked at what makes us delay and found a number of ways to help us stay in the zone. {#blank#}2{#/blank#} Research by Science Focus magazine found silence is best for concentration, or a gentle background music is great! It also found turning off notifications on your phone, or switching it off altogether, removes a major distraction and helps us focus on the task at hand.

  {#blank#}3{#/blank#} Psychologists and neuroscientists are increasingly interested in our ability to settle down and have looked at what we can change inside our head to make us concentrate. An article for BBC Future by Caroline Williams says that "Attention Researcher Nilli Lavie of University College London has found that making a task more visually demanding takes up more processing power and leaves the brain nothing left to process distractions." So, keeping your mind busy might be the answer.

 {#blank#}4{#/blank#} These include making a list or timetable of the tasks you have to do, finding a workspace where you're not attracted by other things, or chewing some gum! It's possible the movement in your mouth occupies parts of the brain that might otherwise get distracted.

But according to Science Focus magazine, distraction isn't all bad. "If we were always so focused that we never got distracted, we'd miss potential changes, such as threats, in our environment. {#blank#}5{#/blank#} ."

A. Distraction is vital for survival.

B. Staying focused can avoid dangers.

C. Performing visual tasks makes us concentrate.

D. One of the most obvious things is removing noise.

E. Staying focused can still be a challenge in adult life.

F. There are more practical tips to keeping your mind focused.

G. Another possible cure for a short attention duration is brain training.