Bottled water has become the choice for people who are healthy and thirsty. Bottled water is all over the world. But some say the planet's health, and people's health may be suffering from it.

    The idea that bottled water is safer for humans may not be true. The Natural Resources Defense Council of America said, “There is no promise that because water comes out of a bottle, it is cleaner or safer than water from the tap.” Another New York City-based action group added that some bottled water is “really just tap water in a bottle—sometimes more clean, sometimes not.”

    It is not proven that bottled water is better than tap water. Nick Reeves from the Chartered Institution of Water and Environmental Management said, “The high mineral content(含量) of some bottled water makes them not good for feeding babies and young children.” Also, most bottled water doesn't have fluoride(氟化物), which can make teeth stronger. Kids are drinking more bottled water and less fluoridated tap water, and some say that's behind the recent rise in bad teeth.

    Storing is another problem. Placed near heat, the plastic bottles can produce bad chemicals(化学物质) into the water.

    According to the Environmental Protection Agency, some 2.7 million tons of plastic are used worldwide to bottle water each year. The plastic can take between 400 and 1,000 years to break down.

    In terms of energy use, plastic bottles are also not cheap. One report said that if water and soft drink bottlers had used 10 percent recycled materials in their plastic bottles, they would have saved about 72 million gallons of gas.

    So, if you are worried about the effect of bottled water on the Earth, you can take the following steps.

●Drink from your tap. Unless your government warns against this, it should be fine.

●Get a container(容器). Carry your tap water in a steel or a lined drinking container, and clean it between uses.

●Keep it cool. Don't drink from a bottle that has been sitting in the sun, don't store it near chemicals, and don't reuse plastic bottles.

●Choose glass containers over plastic if possible. When finished, recycle!

    Neuroscientists have explained the risky, aggressive or just plain baffling behavior of teenagers as the product of a brain that is somehow compromised. Groundbreaking research in the past 10 years, however, shows that this view is wrong. The teen brain is not defective. It is not a half-baked adult brain, either. It has been forged by evolution to function differently from that of a child or an adult.

    The most important of the teen brain's features is its ability to change in response to the environment by modifying the communication networks that connect brain regions. It allows teenagers to make enormous progress in thinking and socialization. But the change also makes them sensitive to dangerous behavior and serious mental disorders.

    The most recent studies indicate that the riskiest behaviors arise from a mismatch between the maturation of networks in the limbic system(边缘系统), which drives emotions at adolescence, and the maturation of networks in the prefrontal cortex（前额皮质）, which occurs later and promotes sound judgment and the control of impulses. Indeed, we now know that one's prefrontal cortex continues to change noticeably until his 20s. And yet adolescence seems to be starting earlier, extending the “mismatch years.”

    The plasticity of networks linking brain regions—and not the growth of those regions, as previously thought—is key to eventually behaving like an adult. Understanding that, and knowing that a widening gap between the development of emotional and judgment networks is happening in young people today, can help parents, teachers, counselors and teenagers themselves. People will better see that behavior such as risk-taking and turning away from parents and toward peers are not signs of cognitive or emotional problems. They are a natural result of brain development, a normal part of adolescents learning how to negotiate with a complex world.

    The same understanding can also help adults decide when to intervene. A 15-year-old girl's departure from her parents' tastes in clothing, music or politics may be a source of anxiety for Mom and Dad but does not indicate mental illness. A 16-year-old boy's tendency to skateboard without a helmet or to accept risky dares from friends is not unimportant but is more likely a sign of short-range thinking and peer pressure than a desire to hurt himself. Knowing more about the unique teen brain will help all of us learn how to separate unusual behavior that is age-appropriate from that which might indicate illness. Such awareness could help society reduce the rates of teen addiction, motor vehicle accidents and depression.

5 books I loved in 2018

By Bill Gates

    A great read is the perfect gift and I think everyone could use a few more books in their lives. My book list covers various topics, including an autobiography on learning throughout a life, a deep search on autonomous weapons (武器), a thriller about the fall of a once­promising company and a guide about meditation (冥想)­there's something for everyone.

    The Head space Guide to Meditation and Mindfulness, by Andy Puddicombe. The book starts with Puddicombe's personal journey from a university student to a Buddhist monk and then becomes an entertaining explainer on how to meditate. If you're thinking about trying mindfulness, this is the perfect introduction.

    Army of None, by Paul Scharre. It's an extremely complicated topic, but Scharre offers clear explanations and presents both the advantages and disadvantages of machine­driven warfare. His fluency with the subject should come as no surprise: he's an ex­soldier who helped draw up the U.S. government's policy on autonomous weapons.

    Bad Blood, by John Carreyrou. Carreyrou gives you the definitive insider's look at the rise and fall of a company. I found myself unable to put it down once I started. This book has everything: magazine cover stories, ruined family relationships, and the failure of a company once valued at nearly $10 billion.

    21 Lessons for the 21st Century, by Yuval Noah Harari. I'm a big fan of everything Harari has written, and his latest is no exception. If 2018 has left you stressed out by the state of the world, 21 Lessons offers a helpful framework for processing the news and thinking about the challenges we face.

    Educated, by Tara West over. Tara never went to school or visited a doctor until she left home at 17. I loved this life story of a young woman whose thirst for learning was so strong that she ended up getting a P.h.D. from Cambridge University.

    An 8-year-old southeast Kansas girl is being praised for her quick, calm thinking. She grabbed the steering wheel(方向盘) and drove the family's SUV when her mother fell unconscious on their highway ride to school.

    Abby Porter and her mom, Shelly, were heading for her school in Riverton when Shelly had a medical emergency. She passed out(昏倒) behind the wheel.

    Abby is a second-grader whose father sometimes lets her drive their tractor. With her mother falling down heavily, Abby leaned over and took the wheel. At some point, Abby even successfully performed a U-turn on the four-lane highway, because she was going home to her daddy, according to Galena Police Chief Larry Delmont.

    "That was at 8:37 in the morning, and there was a lot of traffic," Delmont said. Officer Jimmy Hamilton noticed the SUV going about 20 mph and weaving a bit between the two lanes. He suspected someone was driving under the influence. As he got closer, he noticed the woman fell over in the driver's seat and saw Abby at the wheel.

    Hamilton tried to get in front of Abby's car to slow her down, but she kept switching lanes to avoid bumping into his car. Hamilton got alongside her and told Abby to stop the vehicle, but she didn't know how. He then told her she needed to bump into him to stop the car, but Abby said she didn't want to because she was afraid. He convinced Abby bumping into his car was OK.

    "I never saw her cry," Hamilton said. "From just the expression on her face and the tone of her voice, you could tell she was scared. But she stayed with it."

    Emergency crews got Abby's mother to the hospital, but Delmont said he didn't know what caused her to lose consciousness.

    The police department in Galena, a town of about 3,000 residents about 150 miles south of Kansas City, planned to present Abby with a plaque(匾牌) for "outstanding bravery in a life-threatening situation".

    In many developed countries, people who have high degrees begin to work longer than those who don't. About 65% of American men aged 62－74 with a professional degree are in the workforce (劳动人口), compared with 32% of men who only finish high school. This gap is part of a deepening divide between the well­educated wealthy and the unskilled poor. Rapid technological advance has raised the incomes of the highly skilled while squeezing those of the unskilled. The consequences, for individuals and society, are profound(意义深远的).

    The world is facing an astonishing rise in the number of old people, and they will live longer than ever before. Over the next 20 years the global population of those aged 65 or more will almost double, from 600 million to 1.1 billion. The experience of the 20th century, when greater longevity (长寿) translated into more years in retirement rather than more years at work, has persuaded many observers that this shift (变化) will lead to slower economic growth, while the swelling (渐增的) ranks of pensioners will create government budget problems.

    Policies are partly responsible. Many European governments have abandoned policies that used to encourage people to retire early. Even the better­off must work longer to have a comfortable retirement. But the changing nature of work also plays a big role. Pay has risen sharply for the highly educated, and those people continue to reap (获得) rich rewards into old age because these days the educated elderly are more productive than the preceding (先前的) generation. Technological change may well reinforce (强化) that shift: the skills that complement (补充) computers, from management know­how to creativity, do not necessarily decline with age.

    I was in the seventh grade, and we had moved to New Jersey in November. By then, everyone already had had their own friends, and no one wanted to talk to a new girl. To make things worse, they put me in "Section L". I found out later that everyone called Section L "Loserville". It was sort of an open secret that it was the section for troublemakers and not-so-smart kids. When I found out, I wanted to scream. I had always been a good student and had amazing friends, and now everyone thought I was a loser!

     I did text my friends in Illinois almost every night, especially my best friend, Ana. At first my friends wanted to hear all about it. But then some stopped texting back once I said something about how miserable I was. One night when I was texting with Ana, I complained about another friend who had just done that.

     Ana's texts came really fast for the next few minutes and they surprised me. She said that she was tired of hearing about how bad everything was in New Jersey, too. She said she did not want to hurt my feelings but that I needed to stop feeling so sorry for myself all the time, I had to try to make things better.

     The next day, I thought a lot about what Ana had said. She was right!

     I wish I could say that everything changed overnight after that, but it didn't. I was still stuck in "Loserville", and some people were still mean to me, even though I tried to just stay out of their way.

     But what did change was me—I stopped feeling so sorry for myself and did something about making friends. I signed up to make sets for the school play. I met a lot of new people there, and suddenly I had friends to say hi to in the halls!

     I still miss Illinois sometimes, but life in New Jersey isn't so hard anymore. Even though I couldn't change my situation, I could change my attitude—and that made all the difference.