Here is an astonishing and significant fact：Mental work alone can't make us tire. It sounds absurd．But a few years ago, scientists tried to find out how long the human brain could labor without reaching a stage of fatigue(疲劳). To the amazement of these scientists, they discovered that blood passing through the brain, when it is active, shows no fatigue at all!

    If we took a drop of blood from a day laborer, we would find it full of fatigue toxins (霉素) and fatigue products. But if we took blood from the brain of an Albert Einstein, it would show no fatigue toxins at the end of the day.

    So far as the brain is concerned, it can work as well and swiftly at the end of eight or even twelve hours of effort as at the beginning. The brain is totally tireless. So what makes us tired?

    Some scientists declare that most of our fatigue comes from our mental and emotional (情绪的)attitudes. One of England's most outstanding scientists, J. A. Hadfield, says, “The greater part of the fatigue from which we suffer is of mental origin. In fact, fatigue of purely physical origin is rare. ”Dr. Brill, a famous American scientist, goes even further, He declares, “One hundred percent of the fatigue of sitting worker in good health is due to emotional problems.”

    What kinds of emotions make sitting workers tired? Joy? Satisfaction? No! A feeling of being bored, anger, anxiety, tenseness, worry, a feeling of not being appreciated— those are the emotions that tire sitting workers. Hard work by itself seldom causes fatigue. We get tired because our emotions produce nervousness in the body.

    In the early times,the music industry was terrified of taping,thinking that customers would just copy music,or record from the radio.But that never really happened,at least not enough to cause any real hardship to anyone in the music business.

    The same argument arose over technologies like miniDisc and recordable CDs.But the thing that terrified the music industry more than anything else was the arrival of services like Napster,which allowed people to share music over the Internet without costing them anything.The music industry was shocked: it saw people exchanging digital copies that didn't degrade（降级）with each transfer,something that kept tapes from being a huge threat.

    But it wasn't the Internet that killed the music industry.In fact,everything is still looking optimistic for many musicians.Taylor Swift has had a good year,and her latest album is likely to be making her very wealthy indeed.And that won't change in all likelihood,not for Swift,and not for those who come after her.There is always going to be public demand for music.

    However,the technology will simply destroy the record company.The reason is simple.Record companies are a man in the middle that simply doesn't need to exist anymore.The same way we buy our flights directly did get our shopping online and have things delivered from Amazon instead of going to a local shop.We have always been willing to enjoy cost reductions at the expense of the middleman and the record companies are that kind of middleman.

    What does the record industry offer?Well,surprisingly little these days.It used to be the case that record companies would go and find new talents.Of course this still happens,but more likely is that an artist will be discovered by the public through YouTube,or even from friends on Facebook or Twitter.Record companies also used to have an important role in producing the music.But countless artists are making their own way through software or any of the other amazing music development apps,without any help from the record companies.

    As self — driving cars come closer to being common on American roads, much of the rhetoric (说辞) promoting them has to do with safety. About 40,000 people die on U. S. roads every year, and driver errors are linked to more than 90 percent of crashes. But many of the biggest advocates of autonomous vehicles aren't car companies looking to improve the safety of their existing products. Huge backing for self - driving technologies is coming from Silicon Valley giants like Google and Apple.

    Those of us who have studied the relationship between technology and society tend to look more carefully at the motivations behind any technological push. In this case, it's clear that in addition to addressing safety concerns, Silicon Valley firms have a strong incentive (动机) to create a new venue for increasing the use of their digital devices. Every minute people spend on their mobile phones provides data - and often money - to tech companies.

    At present, digital devices and driving are in conflict: There are serious, often fatal, consequences when drivers use smartphones to talk or to text. Regulators and safety advocates look to resolve dial conflict by banning phone use while driving - as has happened in virtually every state. But the tech companies are taking a different approach. The obvious answer for Silicon Valley is creating an antomobile in which continuous cellphone use no longer poses a threat to anyone.

    In recent years, the amount of time adults spend on their mobile devices has grown rapidly. At the moment, it's around four hours a day for the average adult in the U. S. However, that rapid growth is likely to slow down as people run out of time that ' s available for them to use their devices. Unless, of course, there's a new block of time that suddenly opens up. The average American now spends about 48 minutes in a car every day, a sizable opportunity for increased cellphone use.

    So as the public conversation around autonomous cars highlights the safety advantages, don't forget the tech industry ' s powerful desire for more profits, which goes well beyond simply saving us from ourselves.

    When I was younger, I thought that boys and grown men should not cry. The tears were signs of being weak and a sissy(胆小鬼), which a man is not supposed to be. This was even strengthened in my young mind when the song, Boys Don't Cry, came out in the early 1980s.

    But just this June, I discovered that courage is not all about trying to keep all the pain inside in check. Courage is not all about trying to hide the tears. It is the opposite — the tears strengthen the heart's courage. And I saw this in my father. That day my father cried.

    My 18-year-old sister eloped (私奔) and from it I saw how weak my father's heart was. My sister and I were used to seeing him as an iron-willed figure and authoritarian father.

    For three days after my sister eloped, he would not talk. He would just sit quietly outside our house in the dark. On the fourth night, I sat beside him and asked him to tell me what he felt about everything.

    It has been years since I have laid my hand on my father's shoulder as we have drifted apart (疏远) farther and farther while I was growing up. That night，though, I sensed my father trying to control his pain and I wanted him to be able to let it out. We have all cried over what happened except him. All of us except him.

    The simple touch and my words, "Dad, it is not your fault.", broke my father's dam.

    In the darkness, he began to cry. I felt his shoulders shaking as he whispered, "Where did

    I go wrong? All I ever wanted was for my children to grow up right. Why couldn't your sister wait?"

    I understood then why he preferred to be in the dark. By being there, he hoped to spare his family of a father's pain. His tears, though we did not see them before that night, were there all the same. I saw his courage, that night when my father cried with my hand on his shoulder, and understood his pain.

    Moments before I could lift my case to put it in the plane's overhead locker ahead of our recent holiday to Europe, my father gently urged me to stop. He held the thick handles of the case and lifted it with his thin arms, pushing it into place with a sigh. “You should relax and be the lady, and let me do the heavy tasks,” he said seriously. “In the future, someone special will come into your life and take over such tasks from me, but that will never happen if you do everything yourself.”

    I was stunned into silence. This was not the father I remembered from childhood, who trained me to study hard at school, asked me to earn my own pocket money as a teenager at a local coffee shop, and even taught me household chores so that my life alone in London wouldn't turn into a mess. But then, eight years after I left home and started a new life in the UK, I realized for the first time that my dad still has expectations for me to be like a princess and to stay dependent and delicate, which were considered necessary qualities of women in traditional China.

    Well, that came a little late. Little did Dad know that over the three years of my university life, I moved flats five times all by myself, dragging suitcases of books and clothes, and waiting for the taxi in the rain while holding tight onto cardboard boxes. Meanwhile, living in the UK – a country currently led by a female prime minister – I have never thought there is anything girls cannot do. Most of my female friends are professionals working in the City of London, and after work, we frequently go down to the pub for a drink, just like the guys do – something my mother never did.

    I wondered how I might make Dad understand the new world his little girl has entered. Perhaps one day, he will realize the “someone special” in my life will appreciate my confidence and independence above dependence, and admit that times have changed.

    Facebook is an American online social media and social networking service. The Facebook website was launched on February 4, 2004, by Mark Zuckerberg, along with fellow Harvard College students and roommates.

    The founders had limited the website's membership to Harvard students at first; however, later they expanded it to various other universities, and eventually to high school students as well. Since 2006, anyone who claims to be at least 13 years old has been allowed to become a registered (注册了的) user of Facebook, though differences exist in the youngest age requirement, depending on local laws. Facebook has more than 2 billion monthly active users as of June 2017. As of April 2016, Facebook was the most popular social networking site in the world, based on the number of active user accounts.

    Facebook may be accessed by a large range of desktops, smartphones over the Internet and mobile networks. After registering to use the site, users can create a user profile (简介) showing their names and so on. Users can add other users as "friends", exchange messages, post photos and so on.

    Facebook makes most of its income from advertisements which appear on screen, marketing access for its customers to its users.