The idea of being able to walk on water has long interested humans greatly. Sadly, biological facts prevent us ever accomplishing such a thing without artificial aid—we simply weigh too much, and all our mass pushes down through our relatively small feet, resulting in a lot of pressure that makes us sink.

    However, several types of animals can walk on water. One of the most interesting is the common basilisk Basilicus basilicus, a lizard (蜥蜴)native to Central and South America. It can run across water for a distance of several meters, avoiding getting wet by rapidly hitting the water's surface with its feet. The lizard will take as many as 20 steps per second to keep moving forward. For humans to do this, we，d need huge feet that we could bring up to our ears in order to create adequate w hitting.

    But fortunately there is an alternative : cornflour. By adding enough of this common thickening agent to water (and it does take a lot), you can create a “non-Newtonian” liquid that doesn't behave like normal water. Now, if the surface of the water is hit hard enough, particles(粒子）in the water group together for a moment to make the surface hard. Move quickly enough and put enough force into each step, and you really can walk across the surface of an adequately thick Liquid of cornflour.

    Fun though all this may sound, it's still rather messy and better read about in theory than carried out in practice. If you must do it, then keep the water wings handy in case you start to sink--and take a shower afterward!

Research shows that isolation(隔绝，孤立)is bad for us and associated with certain diseases including depression, high blood pressure and heart disease. Yet teenagers seek isolation by using the device of our times—a screen, screens of all kinds. However, in whatever form, screens are addictive, and addictive from an early age. Research has shown that given the chance, six-month-old babies prefer screens to real human faces.

    Hand in hand with this addiction to screens, we are seeing an explosion of teenage mental health problems. Social media claims to be inclusive, keeping you connected. But it's not. It isolates you from real people. Screens have even been described as being poisonous for teenagers.

    Psychologist Jean Twenge, a professor at San Diego State University, believes today's teenagers are “on the edge” of a major mental health crisis and requestes, “do anything that doesn't involve a screen”. The problem is, she claims, children born between 1995 and 2012 have grown up with a smart phone in their hands, and it has “changed every aspect” of their lives. The number of teenagers who actually see their friends frequently has dropped by more than 40% since 2000. In 2015, only 56% of 17-year-old went on a date, down from 85%. Modern teenagers are slower to learn to drive, or earn money and spend more time at home. They're “on their phone, in their room, alone and often depressed”, she says.

    Some critics, however, say we should encourage our children to spend more time online. Robert Hannigan, former director of GCHQ, said in August that Britain is badly short of engineers and computer scientists, and urged children to develop cyber skill to compete in the digital economy.

    I' m not the first to say that social media is inferior to real human contact, and harms mental health. Studies show teens who spend three hours a day online are 35% more likely to suicide(自杀).

    The suicide rate among girls aged 12 to 14 has more than doubled in a decade.

A few months after we moved to a small city in France, I wanted to meet my husband for lunch at the university where he worked. I got lost. I had to call him for help. One of his friends said to him later, "How could she get lost? She just needed to go straight."

Well, no. That's the problem. You never "just go straight", because France is the land of roundabouts (弯道). Highways, major streets, little village lanes – if you go straight long enough, you'll end up going in circles.

    Even after a year here, I'd still get lost going to the grocery store, or just about anywhere that wasn't within a hundred yards of my house.

I admit I have a horrible sense of direction, can't read a map, and am not such a good driver. Plus, I've been spoiled (宠坏) by living in American cities, where you just indeed need to "go straight". But in France, driving became my nightmare — the roads are roundabouts within roundabouts.

    Finally I found a solution: a GPS program on my smart phone. I rely on it to get anywhere, even places I've been.

    But it does leave me feeling very bad and helpless when, often, the program doesn't work, can't find a GPS signal, or gives wrong information. I'd have to wait until my GPS gets recovered, or else I use my old solution: I call my husband. Is the GPS making us more stupid, or helping us going around more? In my case, it's probably both.

    The World Happiness Report, a United Nations agency report, measures (估量) how happy people are, and why. Norway is the happiest place on earth—beating neighbour Denmark from the number one position.

    Denmark, Iceland, Switzerland and Finland are among the top five, while the Central African Republic came last. Western Europe and North America took up most of the places at the top of table, with the US and UK at 14th and 19th respectively.

    The World Happiness Report mainly depends on asking a simple question of more than 1,000 people every year in more than 150 countries. “Imagine a ladder, with steps numbered from 0 at the bottom to 10 at the top,” the question asks. “The top of the ladder is the best possible life for you and the bottom of the ladder is the worst possible life for you. On which step of the ladder would you say you personally feel you stand at this time?”

    The average (平均的) result is the country's score—from Norway's 7.54 to the central African Republic's 2.69. But the report also tries to explain why one country is happier than another. It looks at reasons including economic strength, social support, freedom of choice, and generosity.

    This year's report also has a text titled “restoring (恢复) American happiness”, which examines why happiness levels in the United States are falling, despite continually-increasing economic improvement. “The United States can and should raise happiness by solving American's social problems—rising inequality and distrust—rather than focusing mainly on economic growth,” the authors said.

    Jeffrey Sachs, the director of the Sustainable Development Solutions Network, which published the report, said President Donald Trump's policies were likely to make things worse.

    In our increasingly fast-paced, technology-driven world, most adults do not get the 8-10 hours of sleep every night. Things are even worse for those with young children. A recent study showed that 86% of parents in the UK complain of tiredness and about 26% get less than 5 hours of sleep every night. To give tired parents a little relaxation from their tight schedules (时间表), David Lloyd Clubs, a chain of gyms and fitness centers in Europe, has introduced a napping (小憩)class!

    As the name suggests, the hour-long group class, described as a way to " refresh the mind, improve moods, and even bum the odd calorie (卡路里)", does not involve any hard exercise. Instead, the members are guided through 15 minutes of light stretching (伸展)to help them relax. Then, they are encouraged to lie under the blankets of a comfortable bed, cover their eyes with an eye mask, and take a nap for 45 minutes. With music playing in the background and the room set to the perfect temperature, they can be assured of the best possible sleep. The class is now being offered at just one place. If popular, they will be expanded (延伸)to other David Lloyd Clubs.

    Do you know the good points of nap? A study conducted by Pennsylvania's Allegheny College found that midday naps not only help participants feel well-rested, but also enable them to deal with stress better. A follow-up study carried out at the University of California at Berkeley concluded that a 45-minute nap in the middle of the day helps to improve the learning abilities. The good news is that you do not have to make a trip to the U. K. to join this latest exercise fashion. You can get involved with the comfort of your own bed. So, go ahead and encourage your entire family to try a napping class.

    If you are worried about the planet, please make sure your rubbish is buried under the ground.

    People talk about "reduce, reuse, recycle." It sounds like a good idea. There is a problem, though. Recycling costs too much money.

    Even the U.S. Environmental Protection Agency (EPA) says it only makes sense economically and environmentally to recycle about 35 percent of disabled (废弃的) materials. Among those materials are paper and aluminum(铝) cans. Recycling 1 ton of paper or aluminum cans, the agency says, can save about 3 tons of CO₂ emissions (排放物) over producing those materials anew. Paper producers pay for the trees they process. If it was cost-effective to recycle paper, producers would be beating down your door to buy it. But they aren't. That means it's more expensive to recycle old paper than to cut trees and then replant trees for processing.

    Plastic can be recycled too. Given the recent drop in crude oil (原油) prices, it is now cheaper to make a new plastic container than to recycle an old one. Even if that were not true, the EPA says that recycling a ton of plastic saves only about a ton of CO₂. However, it doesn't take into account the water most consumers use to wash their plastic containers before having them recycled. The New York Times journalist John Tierney recently wrote, "If you wash plastic in water that was heated by electricity, then the effort of your recycling could be more carbon in the atmosphere."

    Glass is another recyclable material. To reduce greenhouse gas emissions by 1 ton you have to recycle 3 tons of glass. If one includes the cost of collecting glass waste from neighborhoods, and the pollution produced by the collection trucks and the recycling process itself, glass recycling creates more greenhouse gas emissions and is more expensive than making new glass, which comes primarily from sand that exists everywhere.

    If recycling were truly cost-effective, private companies would be lining up at your doorstep to buy your rubbish. Don't look now because they're not there.