In the mid­1950s，I was a somewhat bored early­ado lescent male student who believed that doing_any_more_than_necessary_was_wasted_effort.One day，this approach threw me into embarrassment.

    In Mrs.Totten's eighth­grade math class at Central Avenue School in Anderson，Indiana，we were learning to add and subtract decimals (小数)．

    Our teacher typically assigned daily homework，which would be recited in class the following day.On most days，our grades were based on our oral answers to homework questions.

    Mrs.Totten usually walked up and down the rows of desks requesting answers from student after student in the order the questions had appeared on our homework sheets.She would start either at the front or the back of the classroom and work toward the other end.

    Since I was seated near the middle of about 35 students，it was easy to figure out which questions I might have to answer.This particular time，I had completed my usual two or three problems according to my calculations.

What I failed to expect was that several students were absent，which threw off my estimate.As Mrs.Totten made her way from the beginning of the class，I desperately tried to determine which math problem I would get.I tried to work it out before she got to me，but I had brain freeze and couldn't function.

    When Mrs.Totten reached my desk，she asked what answer I'd got for problem No.14.“I...I didn't get anything，”I answered，and my face felt warm.

     “Correct，”she said.

    It turned out that the correct answer was zero.

    What did I learn that day？First，always do all your homework.Second，in real life it isn't always what you say but how you say it that matters.Third，I would never make it as a mathematician.

    If I could choose one school day that taught me the most，it would be that one.

    We are naturally drawn to friends and colleagues with familiar voices, scientists have found. People prefer those who have a similar accent, intonation and tone of voice to themselves, they discovered.

    Previous research has focused on how male or female a voice sounds. Men with deeper voices and women with slightly higher voices were thought to sound more attractive, because they suggest a bigger or a smaller body.

    But the new study, published by a linguistics expert in Canada, suggests there is a more complex mechanism (机制) at play. Dr Molly Babel, from the University of British Columbia in Canada, said, “The voice is an amazingly flexible tool that we use to construct our identity. Very few things in our voices are changeless, so we felt that our preferences had to be about more than a person's shape and size.”

    She recorded 30 volunteers' voices and asked each to rate the others' attractiveness on a range from one to nine. Each participant was from western America, with similar accents. The people we assessed were all in the same dialect group, but they showed that dialect to different degrees.

     “We seem to like people who sound like we sound, and we like people who fit within what we know,” Dr Babel said. She also found that breathy voices in women—typified by the famous American actress Marilyn Monroe-were seen as more attractive.

    The breathy tone, caused by younger and thinner vocal cords (声带), implied youthfulness and health. A creaky (咯吱作响的) voice, suggesting a person has a cold, is tired or smokes, was seen as unattractive. The participants preferred men who spoke with a shorter average word length and deeper voices.

    You've probably visited the Tian'anmen Gatetower—the landmark building of Beijing, but you may not have heard of Kuai Xiang. Along with him, the following remarkable architects all took the center stage at their times.

    Kuai Xiang(1399—1481)

    Tian'anmen Gatetower is universally considered the brainchild of Kuai Xiang. By following in the footsteps of ancient homebuilders, he successfully presented the Emperor Judy with a grand wooden structure which has stood the test of time for almost 600 years. Visitors are also hooked on its delicate paintings.

    Ieob Ming Pei (1917-present)

    His motto is: Traditions should be sealed in glass boxes at museums. He is always struggling with innovation. Although under grilling from French conservative critics, he still planted a glass pyramid into the courtyard of the Louvre. His other works include John F. Kennedy Library, Beijing Fragrant Hill Hotel and Suzhou Museum.

    Zaha Hadid(1950-2016)

    In 2004, she became the first woman to win the Pritzker Architecture Prize, the Nobel Prize for architecture. She used tricks to maximize available space. Her fluid-style works pioneer the concept of micro-living. The curves(曲线) of Guangzhou Opera House perfectly match the rise and fall of its surrounding buildings, forming a unique view.

    Meng Fanchao (1959-present)

    Many people dismissed the building of a mega bridge as a pipe dream, but Meng Fanchao turned this into reality by building Hong Kong-Zhuhai-Macao Bridge. This longest cross-sea bridge, when viewed afar, looks like a dynamic dragon braving the rolling waves of Lingding Sea.

    When most people think of the word, “brand”, they think of the Nike Swoosh, Ford “blue oval,” McDonalds Golden Arches, or the “State Farm is There” jingle. They know what they will get with a well branded product or service as promised. Think of Volvo, for instance, and your first thoughts are probably something like “well built, comfortable, Swedish” and, most of all, “safety”.

    So a brand is a lot more than a logo, icon, or slogan. Catchy as it may sound, it isn't the “brand” in the true sense—and it certainly isn't what makes the brand valuable. A company's brand is a promise. It's a description of the company's character. To some extent, it's a mission; it's how the company creates and delivers value. Also, it's the feeling the company conveys to its stakeholders. Successful brands meet various challenges and consistently deliver on their promises, which is how they create brand value. To illustrate it, here are some brand promises from three highly successful, world-wide brands: The NFL: “To be the premier sports and entertainment brand that brings people together, connecting them socially and emotionally like no other.” Coca-Cola: “To inspire moments of optimism and uplift.” Virgin Atlantic: “To be genuine, fun, contemporary, and different in everything we do at a reasonable price.”

    Interesting. In none of the above cases does the brand promise describe what these companies do or provide. The NFL's brand promise says nothing about football. Coca-Cola doesn't talk about providing the best soft drinks in the world. And Virgin Atlantic's promise goes a lot farther than seating passengers in its aircrafts.

    Of course, a promise is nowhere near enough. The promise along with look, personality, time, money, and hard work combined can eventually help to build and maintain great brands and acquire a special patina(光泽) of what I call “me” appeal, showing my personal appetite. Apple has that patina. All of this can lead to sub-brands, like iPhone and iPad which acquire the glory of the parent brand.

    Sometimes a brand is memorable because of little things. TD Bank has a special place in their branches for you to deposit all those coins you collect in jars. It is called the Penny Arcade that turns depositing your coins into a fun game in which you can even win prizes. Years ago, Dime Savings Bank in New York had a small dime(十分硬币) carrier. It was given to kids and then they'd fill up its 50 slots (投币口) with a dime in each one and bring it to exchange for a $5 bill.

    Are your eyes irritated, dry, watery, blurry, seeing double or sensitive to light, and do your back and neck ache? If so, you are likely one of many people today who suffer from digital eyestrain, also called computer-vision syndrome.

    Eyestrain is often related to the amount of exposure to screens, the distance from eyes to screens and the use of multiple screens simultaneously. However, studies have also shown that the blue light produced by digital devices today reaches further into the eyes than other kinds of light. This light actually assists attention during the day but can result in interrupted sleep patterns at night.

    Scientists have also said that eyestrain is not a necessary evil, even in a modern world that revolves around technology. Changing some simple details about your relative position to screens, such as staying about 60 centimeters away, will help. Also, avoid overhead and other direct sources of light, and use shaded lamps and window blinds while looking at digital devices instead.

    Beyond the way that relates to digital screens, there are also ways to change how you view screens that are helpful in combating eyestrain. To begin with, your computer screen should be high-resolution(高清的), at least 50 centimeters wide diagonally and may require a screen filter to decrease reflections. Also, be aware that "computer glasses", which cut down glare and blue light, are available and those contact lenses can increase the risk of eyestrain.

    Besides, to reduce your risk for computer-vision syndrome and neck, back and shoulder pain, take frequent breaks during your computer workday. Many workers take only two 15-minute breaks from their computer throughout their day. According to a recent study, discomfort and eyestrain are significantly reduced when computer workers take four additional five-minute "mini-breaks" throughout their workday. And these additional breaks don't reduce the workers' productivity.

    Finally, many of us fall into bad habits while using digital screens that only worsen the effects of eyestrain. While viewing digital screens, many people blink one third less often than they usually do. Place a reminder on your computer to "blink" so that your eyes don't dry out. Also, rest your eyes' focusing muscles by using the 20-20-20 rule: Every 20 minutes, focus on something 20 feet away for 20 seconds.

    Most dog owners have probably been puzzled waiting for their dog to do its business. Instead of just finding a soft area of grass to go number two, they make a whole ritual(仪式) out of it, spinning in a circle before finally squatting(蹲下). Luckily, the ultimate pet owners' question may finally have been answered.

    A few theories have circulated about why dogs might circle before pooping  and most are similar to the reasons they spin before lying down. Trampling around in a circle would flatten the grass around, which would keep tall blades(叶片) from trapping their waste. Another explanation could be that they're scanning for snakes and predators before they become completely occupied.

    But Czech researcher Hynek Burda didn't quite buy into those theories. Dogs evolved from wolves, which didn't need to worry much about tall grass. And if they were scanning their environment, keeping still to listen and sniff would be more effective than giving the area a quick once-over. Instead, Burda suggested that dogs spin to get a feel for the Earth's magnetic pull.

    The Earth has a magnetic field around it protecting it from radiation from space, and some animals seem to use it to get a sense of where its North and South poles are. For instance, it's how birds know which way to migrate. In 2013, Burda published a study in the journal Frontiers in Zoology suggesting dogs have a strong internal compass, too. He and his team spent two years watching 70 dogs poop and pee and recording which way they faced and how strong the magnetic(磁的) field was.

    As it turns out, when the magnetic field was calm, dogs preferred to poop facing either north or south.

    The pattern couldn't explain why dogs like facing the Earth's poles, but the researchers think it might help them remember where they marked their territory.

    If they can remember which way they were facing, they might find it easier to find that spot again. So before you roll your eyes when your dog takes ages to do his business, remember that Fido might just be getting scientific about his potty spot.