Ever wonder how much a cloud weighs? What about a hurricane? A meteorologist（气象学家） has done some estimates and the results might surprise you.

    Let's start with a very simple white puffy cloud—a cumulus cloud(积云). How much does the water in a cumulus cloud weigh? Peggy LeMone, senior scientist at the National Center for Atmospheric Research in Boulder, Colorado, did the numbers. “The water in the little cloud weighs about 550 tons,” she calculates. “Or if you want to convert it to something that might be a little more meaningful...think of elephants.” Assume（假设） an elephant weighs about six tons, she says, that would mean the water inside a typical cumulus cloud would weigh about one hundred elephants.

    The thought of a hundred elephants' worth of water floating in the sky begs another question—what keeps it up there?

    “First of all, the water isn't in elephant-sized particles(微粒); it's in tiny tiny tiny particles,” explains LeMone. And those particles float on the warmer air that's rising below. But still, the concept of so much water floating in the sky was surprising even to a meteorologist like LeMone. “I had no idea how much a cloud would weigh, actually, when I started the calculations（计算）,” she says.

    So how many elephant units of water are inside a big storm cloud—10 times bigger all the way around than the “puffy” cumulus cloud? Again, LeMone did the numbers: About 200,000 elephants.

    Now, come to the calculations for a hurricane about the size of Missouri and the figures get really massive. “What we're doing is weighing the water in one cubic meter theoretically pulled from a cloud and then multiplying by the number of meters in a whole hurricane,” she explains.

    The result? Forty million elephants. That means the water in one hurricane weighs more than all the elephants on the planet. Perhaps even more than all the elephants that have ever lived on the planet.

    Our brains work in complex and strange ways.There are some people who can calculate the day of the week for any given date in 40,000 years,but who cannot add two plus two.Others can perform complex classical piano pieces after hearing them once,but they cannot read or write.

    Dr.J.Langdon Down first described this condition in 1887.He called these people idiot savants.An idiot savant is a person who has significant mental impairment（损伤）,such as in autism（孤独症，自闭症）or retardation.At the same time,the person also exhibits some extraordinary skills,which are unusual for most people.The skills of the savant may vary from being exceptionally gifted in music or in mathematics,or having a photographic memory.

    One of the first descriptions of a human who could calculate quickly was written in 1789 by Dr.Benjamin Rush, an American doctor.His patient,Thomas Fuller,was brought to Virginia as a slave in 1724.It took Thomas only 90 seconds to work out that a man who has lived 70 years,17 days,and 12 hours has lived 2,210,500,800 seconds. Despite this ability,he died in 1790 without ever learning to read or write.

    Another idiot savant slave became famous as a pianist in the 1860s.Blind Tom had a vocabulary of only 100 words,but he played 5,000 musical pieces beautifully.

    In the excellent movie Rain Man,made in 1988 and available on video cassette,Dustin Hoffman plays an idiot savant who amazes his brother played by Tom Cruise,with his ability to perform complex calculations very rapidly.

    Today we more clearly recognize that the idiot savant is special because of brain impairment.Yet not all brain impairment leads to savant skills.Some studies have shown that people who have purposeful interruption of the left side of the brain can develop idiot savant skills.However few people wish to participate in such experiments.There are many excellent reasons for not undergoing unnecessary experimentation on one's brain.The term idiot savant is outdated and inappropriate.Virtually all savants have a high degree of intelligence and are thus not idiots.

    When her five daughters were young, Helen An always told them that there was strength in unity (团结). To show this, she held up one chopstick, representing one person. Then she easily broke it into two pieces. Next, she tied several chopsticks together, representing a family. She showed the girls it was hard to break the tied chopsticks. This lesson about family unity stayed with the daughters as they grew up.

    Helen An and her family own a large restaurant business in California. However, when Helen and her husband Danny left their home in Vietnam in 1975, they didn't have much money. They moved their family to San Francisco. There they joined Danny's mother, Diana, who owned a small Italian sandwich shop. Soon afterwards, Helen and Diana changed the sandwich shop into a small Vietnamese restaurant. The five daughters helped in the restaurant when they were young. However, Helen did not want her daughters to always work in the family business because she thought it was too hard.

    Eventually the girls all graduated from college and went away to work for themselves, but one by one, the daughters returned to work in the family business. They opened new restaurants in San Francisco and Los Angeles. Even though family members sometimes disagreed with each other, they worked together to make the business successful. Daughter Elizabeth explains, “Our mother taught us that to succeed we must have unity, and to have unity we must have peace. Without the strength of the family, there is no business.”

    Their expanding business became a large corporation in 1996, with three generations of Ans working together. Now the Ans' corporation makes more than $ 20 million each year. Although they began with a small restaurant, they had big dreams, and they worked together. Now they are a big success.

    If anyone knows what makes a great children's book,it must be Sussex author and illustrator(插图家) Jane Hissey. Her " Old Bear" books have achieved classic status in a variety of formats.

    I caught up with Jane at her home in the East Sussex countryside and asked her what she thinks is the secret of a classic children's book. "That's a difficult one. I suppose it's got to be relevant to the child's stage of development-for young children, pictures on a page that are familiar, for older children, an experience. The book should be familiar,but hold some surprises too to keep the interest. It must inspire and delight, but there are the things that happen every day. "

    After the birth of her first child,she gave up teaching and worked on her own artwork, drawing pictures of teddy bears. An editor from a publishing company saw her work and invited Jane to do a children's book. Over the years, from the first " Old Bear" book in 1988,her children have made a huge contribution-not least in terms of plot. She said, "I used to give my children the toys to play with-and they had tea parties and so on. One of my bear characters,"Little Bear",is the same age as Ralph, my youngest, who's seven now. All the children have joined in my work and,in years to come, they will realize how much. "

    "I hope I'll know when people are getting tired of the characters. If ever they did, I think I'd go on drawing them for fun," Jane continued," My own children have been very useful to me in my work, but as they are older now, I'll just have to hope that other people's children can inspire me. "

    Being "young is associated with all the good things in life - beauty, hope, and energy. But youth also has negative associations - impulsiveness, trouble -making, and irresponsibility. This negative side seems to be what society focuses on more, which is why young people have mostly been considered as idle and difficult.

    But when it comes to Generation Z - those born between 1996 and 2010 - this stereotype doesn't seem to apply anymore.

    In Japan, for example, Gen Z-ers are less likely to buy on impulse, but take into consideration more a product's true value. They're looking at the companies, not just the products, "Masahiko Uotani, CEO of Japanese cosmetics company Shiseido, told Bloomberg. They're asking, 'Are they really delivering value to the society? Are they promoting diversity and inclusion?"

    Gen Z-ers are also more grounded than we've expected them to be. According to a recent survey by Bank of America, more than half of young adults aged between 18 and 23 said they were planning to buy a house within five years. And they're not just saying it - they are willing to make sacrifices for it, including getting a second job and saving money for down payment instead of spending it on a vacation.

    "Despite their young age, this group is pragmatic and actively planning for their future," D.Steve Boland, head of Consumer Lending at Bank of America, told USA Today. "They have a clear vision how they are willing to help themselves in order to make it happen."

    Social issues are also at the center of concern of Gen Z-ers, who take themselves as a changing force of the world. In India, for example, young people who have just reached the voting age are eager to vote for a new leader who is capable of solving problems that matter the most to them, including pollution, unemployment and women's safety.

    As a Gen-Zer yourself, what is your plan for the future?

    China's popular "Singles' Day", better known as "Double Eleven", started out as a day to celebrate singles symbolized by the four number ones on the date of November 11.

    With time that meaning has changed. In 2009, China's e-commerce leader Alibaba set the day as a lucky shopping day for online sales as the date was both easy to remember and perfectly timed as it hit between the consumer spending lull (间歇) between National Day and Chinese New Year. It soon became a hit, and Double Eleven became a buying frenzy (疯狂) spread across the world's second largest economy.

    In 2019, the Double Eleven Shopping Festival entered its eleventh year. During this decade, Alibaba, Chinese e-commerce giant, and other e-commerce platforms, together with consumers, have co-created a very big shopping event whose heat has swept the world. Foreign readers share their ideas on Singles' Day in China:

    GhostBuster (UK) I think Double Eleven is unbelievable. It is not a religious festival that people of the same religion but living in different countries share. As an e-commerce faithful fan, I really love the shopping festival.

    Emanreus (Australia) I work in Shanghai. Many of my young female colleagues are still single. They simply haven't time to date, as they tend to work long hours then travel two hours by subway to get to and from work. Single's Day is a day when they give themselves a treat with online shopping.

    BlondeAmber (Ireland) There is not hing to be proud of to be in a country that spends so much online on a particular day. It does nothing more than show the superficiality (肤浅) of the temporary pleasure of shopping, and produces nothing more than a mountain of environmental waste. I bet there is plenty of buyers' deep regret after this day.

    Ionstar (US) Singles Day became a big deal for Valentine's Day not for the singles! Well, Alibaba's 11. 11 has become more famous and important than that of Black Friday and Cyber Monday!