The evidence for harmony may not be obvious in some families. But it seems that four out of five young people now get on well with their parents, which is the opposite of the popularly-held image of unhappy teenagers locked in their room after endless family quarrels.

    An important new study into teenage attitudes surprisingly shows that their family life is more harmonious than it had ever been in the past. “We were surprised by just how positive today's young people seem to be about their families,” said one member of the research team. “They're expected to be rebellious(叛逆的) and selfish but actually they have other things on their minds: they want a car and material goods, and they worry about whether school is serving them well. There's more negotiation(商议) and discussion between parents and children, and children expect to take part in the family decision-making process. They don't want to rock the boat.”

    So it seems that this generation of parents is much more likely than parents of 30 years ago to treat their children as friends. “My parents are happy to discuss things with me and willing to listen to me,” says 17-year-old Daniel Lazall. “I always tell them when I'm going out clubbing. As long as they know what I'm doing, they're fine with me.” Susan Crome, who is now 21, agrees. “Looking back on the last 10 years, there was a lot of what you could call negotiation. For example, as long as I'd done all my homework, I could go out on a Saturday night. But I think my grandparents were a lot stricter with my parents than that.”

    Maybe this positive view of family life should not be unexpected. It is possible that the idea of teenage rebellion(反抗) is not rooted in real facts. A researcher comments, “Our surprise that teenagers say they get along well with their parents comes because of a brief period in our social history when teenagers were regarded as different beings. But that idea of rebelling and breaking away from their parents really only happened during that one time in the 1960s when everyone rebelled. The normal situation throughout history has been a smooth change from helping out with the family business to taking it over. ”

    Are you an optimist? Do you look at your glass and see it as half full? Do you believe that every cloud has a silver lining and that generally things turn out for the best? Do you believe that if something is meant to be, it will be? If you reply "yes" to all of these questions, then you are an optimist. You probably are enthusiastic, cheerful and outgoing. You may well be successful at work and in love.

    But you may be misguided because things don't turn out for the best. You may believe that when one door closes another one opens (For example, you may fail to land a new job, but another chance will come around soon). Wrong. When one door closes, another door slams in your face. That's bitter reality.

    Now a book has been published which confirms what we pessimists(悲观者) have suspected all along. It's called The Positive Power of Defensive Pessimism. Its author argues that defensive pessimism can lead to positive results. Defensive pessimism is a strategy used to manage fear, anxiety and worry. Defensive pessimists prepare for things by setting low outcomes for themselves. They carefully consider everything that may go wrong and plan for ways to handle these problems. And this gives them a sense of control. Lawrence Sanno, a psychology professor, says, "What's interesting about defensive pessimists is that they tend to be very successful people, so their low opinion of the situation's outcomes is not realistic. They use it to motivate themselves to perform better."

    So far, so good. This is not rocket science. Defensive pessimists prepare carefully and consider what might go wrong, whether at work, on a date or even in a sports game. It makes sense to have a backup plan. There are many sayings in English urging caution. For example, "Don't put all your eggs in one basket", and "Don't count your chickens until they hatch." To have a confident and optimistic approach to life's problems is good. But listen to what Woody Alien, the American comedian says, "Confidence is what you have before you understand the problem."

    There are pros and cons to being an optimist and a pessimist. Don't feel bad if you see the glass half empty. You are a realist. But lighten up and hook up with someone who sees the same glass half full.

    A black hole is created when a large star burns out. Like our sun, stars are unbelievably hot furnaces(熔炉) that burn their own matter as fuel. When most of the fuel is used up, the star begins to die.

    The death of a star is not a quiet event. First there is a huge explosion. As its outer layer is blasted off into space, the dying star shines as brightly as a billion suns.

    After the explosion, gravity pulls in what's left of the star. As the outside of the star sinks toward the center, the star gets smaller and smaller. The material the star is made of becomes tightly packed together. A star is so solid that a teaspoon of matter from it weighs billions of pounds.

    The more the star shrinks(收缩), the stronger the gravity inside it becomes. Soon the star is very tiny, and the gravity pulling it in is unbelievably strong. In fact, the gravity is so strong that it even pulls light into the star! Since all the light is pulled in, none can go out. The star becomes black when there is no light. Then a black hole is born!

    That's what we know about black holes. What we don't know is this: What happens inside a black hole after the star has been squeezed into a tiny ball? Does it keep getting smaller and smaller forever? Such a possibility is hard to imagine.

    But if the black hole doesn't keep shrinking, what happens to it? Some scientists think black holes are like doorways to another world. They say that as the star disappears from our universe, it goes into another universe. In other words a black hole in our universe could turn into a "white hole" in a different universe. As the black hole swallows(吞噬) light, the white hole shines brightly--somewhere else. But where? A different place, perhaps, or a different time--many years in the past or future.

    Could you travel through a black hole? Right now, no. Nothing we know of could go into a black hole without being crushed(挤压). So far the time being, black hole must remain a mystery.

Black holes are a mystery--but that hasn't stopped scientists from dreaming about them. One scientist suggested that in the future we might make use of the power of black holes. They would supply all of Earth's energy needs, with plenty to spare. Another scientist wondered if a black hole could some day be used to swallow earthly waste--a sort of huge waste disposal(处理) in the sky!

    Bargain hunters spent a record of 168.2 billion yuan ($25.3 billion; 21.7 billion euros; ￡19.3 billion) during the 2017 Singles Day on Nov. 11, the world's largest daylong discount festival, as e-commerce giant Alibaba Group took online shopping to offline stores and beyond(超越) the nation's borders(边界).

    Spending climbed by 39.3 percent during this year's sale, as consumers from 225 countries and regions scooped up goods from 140,000 brands (品牌)that offered promotions during the annual event.

    Alibaba surpassed last year's 120.7 billion yuan total shortly after 1 pm, as overseas shoppers joined in the afternoon, seeking good deals from China. Expanding at a faster-than-expected pace, the total eclipsed (使黯然失色) the combined sales of Black Friday and Cyber Monday in the United States last year. Nine out of ten people used mobile wallet apps for payment, says Alibaba, with its Alipay app having handled 1.48 billion transactions (转账) in 24 hours and processed them at a peak rate of 256,000 transactions per second.

    Meanwhile, some offline shops also joined in, turning into smart stores that allowed shoppers to track product availability at other locations and get timely delivery to their doorsteps while paying with their phone. "Using big data analytics powered by Chinese tech firms can help us locate customers in a precise manner, something we wouldn't have achieved using old-school retailing," says Gary Chu, e-commerce general manager.

    The Nov. 11 shopping event represents a China-branded business model that can also be spread to other countries, creating opportunities for businesses worldwide. As Singles Day grows, shoppers have used the opportunity to try out new items rather than simply bagging a bargain, says Tommy Hong, vice-president of Nielsen China.

    "That changing attitudes (toward Singles Day) is also consistent with China's shifting focus from quantity(数量) to quality growth," Gary Chu says.

    Sagrada Familia (2, 056, 448 visits/year)

    Opening hours: 09: 00-18: 00 (October-March)    09: 00-20: 00 (April-September).

    Admission: $11, or $10 with the Barcelona Card.

    Disabled access: Yes

    The temple has been under construction since 1882 and they've still got another 30 to 80 years to go before it will be finished. The project's vast scale (规模) and its special design have made it one of Barcelona's top tourist attractions for many years.

    La Pedrera (1, 133, 220 visits/year)

    Opening hours: 09: 00-18: 30 (November-February)    09: 00-20: 00 (March-October)

    Admission: $9. 50. Save 20% with the Barcelona Card.

    Disabled access: No.

    This building used to be called Casa Mila, but nowadays it's more commonly known as La Pedrera. It was made of bricks and had colorful tiles (瓷砖).

    Barcelona FC Museum (1, 032, 763 visits/year)

    Opening hours: 6th April-4th October: (Monday to Saturday) 10:00-20:00; the rest of the year: 10: 00 to 18: 30.

    Admission: $8. 50 for entry to museum and an extra $17 for a guided tour.

    Disabled access: Yes.

    It is now generally considered as the best football museum in the world. You can see so many trophies (奖杯), pictures and statues of great football players. I'm not a football fan but I still enjoyed walking round this museum.

    Miró Museum (518, 869 visits/year)

    Opening hours: Check website for details as they vary depending on the time of the year.

    Admission: $8. Save 20% with the Barcelona Card.

    Disabled access: Yes.

    This museum has a wide range of Miró's works dating back as far as 1914. This artwork collection includes not only his paintings but also a good selection of sculptures.

According to a new Agriculture Department report, U. S. forests could exacerbate global warming because they are being destroyed by natural disasters and are losing their ability to absorb planet-warming gases as they get older. The report predicts that the ability of forests to absorb carbon will start declining after 2025 and that forests could release up to 100 million metric tons of carbon a year as their emissions (排放) from decaying (腐烂的) trees go beyond their carbon absorption. Forests could become a "substantial carbon source" by 2070, the USDA report says.

The loss of carbon absorption is driven in part by natural disasters such as wildfires, tornadoes and hurricanes, which are increasing in frequency and strength as global temperatures rise. The disasters destroy forestland, destroying their ecosystem and decreasing their ability to absorb carbon, according to Lynn Riley, a senior manager of climate science at the American Forest Foundation. Aging forests also contribute. The report found that older, mature trees absorb less carbon than younger trees of the same species, and U. S. forests are rapidly aging.

This trend is likely to continue, as forests come under increasing threat from climate change and exploitation (开采). The typical tropical (热带的) forest may become a carbon source by the 2060s, according to Simon Lewis, professor in the school of geography at Leeds University. "Humans have been lucky so far, as tropical forests are cleaning up lots of our pollution, but they can't keep doing that indefinitely," he said. "We need to cut down fossil fuel emissions before the global carbon cycle starts working against us."

U. S. forests currently absorb 11 percent of U. S. carbon emissions, or 150 million metric tons of carbon a year, equal to the combined emissions from 40 coal power plants, according to the report. The loss of forests as natural carbon absorbers will require the U. S. to cut emissions more rapidly to reach net zero. "As we work to decarbonize (碳减排), forests are one of the greatest tools at our handling. If we were to lose that, it means we will contribute that much more in emissions." Riley said.