The term “to extend an olive（橄榄） branch” means to make an offer of peace or reconciliation(和好). This term has Biblical（圣经的）origins, coming from the section of the Old Testament that deals with the flood; the sign that the flood is over is an olive branch brought back to the ark(方舟) by a dove. Olive branches were also symbols of peace in Ancient Greece and Rome, and they continue to be used in various works of art that are meant to suggest peace.

    Some people have suggested that the olive was a very deliberate and well-considered choice as a metaphor(比喻）for peace, because olive trees famously take years to mature. War is typically very hard on the trees because people cannot take the time to nurture them and plant new ones. Therefore, the offer of an olive branch would suggest that someone is tired of war, whether it is an actual war or a falling out between friends.

    In Ancient Greek and Roman times, people would offer actual olive branches. In Rome, for example, defeated armies traditionally carried olive branches to indicate that they were giving in, and the Greeks used them into weddings and other ceremonies. In the modern era, the branch is usually metaphorical, rather than actual, not least because the plants can be a bit difficult to obtain.

    Many people agree that peace negotiations at all levels of society are a good idea. Between nations, obviously, it is important to extend an olive branch to ensure mutual safety and to help the world run more smoothly. This act can also be important on a personal level, as resolving conflict and learning to get along with others is viewed as an important life skill in many cultures.

    At some point in their lives, many people will be advised to extend an olive branch to settle a dispute or resolve an issue. Some people believe that it takes an immense amount of courage to take this action, as it often comes with an admission of wrongdoing and regret.

    Have you ever wondered why birds sing? Maybe you thought that they were just happy. After all, you probably sing or whistle(吹口哨) when you are happy.

    Some scientists believe that birds do sing some of time just because they are happy. However, they sing most of the time for a very different reason. Their singing is actually a warning to other birds to stay out of their territory.

    Do you know what a “territory” is? A territory is an area that an animal, usually the male, claims as its own. Only he and his family are welcome there. No other families of the same species(物种) are welcome. Your yard and house are your territory where only your family and friends are welcome. If a stranger should enter your territory and threaten you, you might shout. Probably this would be enough to frighten him away.

    If so, you have actually frightened the stranger away without having to fight him. A bird does the same thing. But he expects an outsider almost any time, especially at nesting(筑巢) season. So he is screaming all the time, whether he can see an outsider or not. This screaming is what we call a bird's song, and it is usually enough to keep an outsider away.

    Birds sing loudest in the spring when they are trying to attract a mate（配偶）and warn others not to enter the territory of theirs.

    You can see that birds have a language all their own. Most of it has something to do with attracting mates and setting up territories.

    Old age may not sound exciting.But recent findings offer good news for older people and for people worried about getting older.Researchers found that people become happier and experience less worry after they reach the age of fifty.In fact，they say by the age of eighty­five，people are happier with their life than they were when they were eighteen years old.

    The findings came from a survey of more than three hundred forty thousand adults in the United States.The Gallup Organization questioned them by telephone in 2008.At that time，the people were between the ages of eighteen and eighty­five.The researchers asked questions about emotions like happiness，sadness and worry.They also asked about mental or emotional stress.

    Arthur Stone in the Department of Psychiatry and Behavioral Science at Stony Brook University in New York led the study.His team found that levels of stress were highest among adults between the ages of twenty­two and twenty­five.The findings showed that stress levels dropped sharply after people reached their fifties.

    The study also showed that men and women have similar feeling patterns as they grow older.However，women at all ages reported more sadness，stress and worry than men.

    Researchers say they do not know why happiness increases as people get older.One theory is that，as people grow older，they grow more thankful for what they have and have better control of their feelings.They also spend less time thinking about bad experiences.

    Professor Stone says the emotional patterns could be linked to changes in how people see the world，or maybe even changes in brain chemistry.

    The researchers also considered possible influences like having young children，being unemployed or being single.But they found that influences like these did not affect the levels of happiness and well­being related to age.

People aren't walking any more—if they can figure out a way to avoid it.

    I felt superior about this matter until  the other day I took my car to mail a small parcel. The journey is a matter of 281 steps. But I used the car. And I wasn't in ay hurry, either, I had merely become one more victim of a national sickness: motorosis.

    It is an illness to which I had thought myself immune（免疫的）, for I was bred in the tradition of going to places on my own two legs. At that time, we regarded 25 miles as good day's walk and the ability to cover such a distance in ten hours as sign of strength and skill. It did not occur to us that walking was a hardship. And the effect was lasting. When I was 45 years old I raced –and beat—a teenage football player the 168 steps up the Stature of Liberty.

Such enterprises today are regarded by many middle-aged persons as bad for the heart. But a well-known British physician, Sir Adolphe Abrhams, pointed out recently that hearts and bodies need proper…… is more likely to have illnesses than one who exercises regularly. And wlaking is an ideal form of exercise— the most familiar and natural of all.

    It was Henry Thoreau who showed mankind the richness of going on foot. The man walking can learn the  trees, flower, insects, birds and animals, the significance of seasons, the very feel of himself as a living creature in a living world, He cannot learn in a car.

    The car is a convenient means of transport, but we have made it our way of life. Many people don't dare to approach Nature any more; to them the world they were born to enjoy is all threat. To them security is a steel river thundering on a concrete road. And much of their thinking takes place while waiting for the traffic light to turn green.

    I say that the green of forests is the mind's best light. And none but the man on foot can evaluate what is basic and everlasting.

    Skiing has always been a big part of Kamikaze shiffrin's life. Her dad ski raced all through college and her mom raced and coached skiing. The Siffrins taught Mikaela and her brother, Taylor. To ski at a very young age. At two and a half years old, Mikaela made her first ski run down her driveway on plastic skis.

    Mikaela loved skiing. From ages 8 to11, she did hundreds of training runs on small hills to learn the skills of slalom skiing (障碍滑雪). When Mikaela was 11, she began to learn at the Burke Mountain Academy, a Vermont boarding school for skiers. She took classes, studied, and practiced her skiing. According to Burke Mountain Academy headmaster Kirk Dwyer, "What separated Mikaela from others was the degree of her commitment (投入) to be the best. Mikacla practiced more than anyone and believed in herself then and now." At age 14, Mikaela began her international career when she raced in the world championship for13 and 14 -year-olds. And she won!

    By the time she was17, she had already won her first World Cup race. "Living away from home four and five months at a time can be difficult" Mikaela says. "But it can also be exciting. I'm getting to see the world." When Mikaela began ski racing in Europe, her mother, Eileen, stayed with her. She worked as her high school teacher while they were on the road. "She has always been a super-hard worker," says Eileen.

    For Mikaela, working hard is a full-time job. Even her off-season is work time. "If you want something, just try your best," she says. At the 2014 Winter Olympic Games in Sochi, Russia, 18-year-old Mikaela Siffrin became the youngest slalom skier ever to win an Olympic gold medal.

Intelligence is traditionally viewed as the ability to think and learn. Yet in a complex world, there's another set of cognitive (认知的) skills that might matter more: the ability to rethink. Therefore, my aim in this book is to explore how rethinking happens by seeking out the most convincing evidence and some of the world's most skilled rethinkers.

The first section focuses on opening our own minds. You'll find out why a forward-thinking businessman got trapped in the past, how a Nobel Prize-winning scientist welcomes the joy of being wrong, how the world's best forecasters update their views, and how an Oscar-winning filmmaker has productive fights.

The second section examines how we can encourage other people to think again. You'll learn how an international debate champion wins arguments and an African-American musician persuades people to abandon discrimination (歧视). You'll discover how a special kind of listening helped an officer convince the opposing side to join in peace talks. And if you're a Yankees fan, I'm going to see if I can convince you to root for the Red Sox.

The third section is about how we can create communities of lifelong learners. In social life, a lab that specializes in difficult conversations will cast light on how we can communicate better about debated issues like climate change. In schools, you'll find out how educators teach kids to think again by treating classrooms like museums, and approaching projects like rewriting time-honored textbooks. I close by examining the importance of reconsidering our best-laid plans.

This book is an invitation to let go of knowledge and opinions that are no longer serving you well, and to establish your sense of self in flexibility rather than consistency. If you can master the art of rethinking, I believe you'll be better positioned for success at work and happiness in life. Thinking again can help you generate new solutions to old problems and revisit old solutions to new problems. It's a path to learning more from the people around you and living with fewer regrets.