I had to knock on the taxi to get his attention. Finally, the driver, a man about 60, looked up from behind the wheel and apologized, “I'm sorry, but I was reading a letter.” He sounded as if he had a cold or a cough.

    Since I was in no hurry, I told him to finish his letter. He shook his head, explaining that he had already read it several times and almost knew it by heart. Curious, I asked whether it was from a child or maybe a grandchild. “This isn't family,” he replied. “though he might just as well have been a regular member of the family. Old Ed and I grew up together.”

    They were always friends. But since he moved away from the neighborhood 30 years ago, it'd generally just been postcards at Christmas time between them. A couple of weeks ago, Ed died. “I should have kept in touch.” He repeated this, more to himself than to me. To comfort him, I said sometimes we just didn't seem to find the time. “But we used to find the time,” he said. “Take a look.” He handed the letter over to me.

    The first sentence “I've been meaning to write for some time, but I've always delayed it.” reminded me of myself. It went on to say that he often thought about the good times they had had together. When I read the part where it said “Your friendship really means a lot to me, more than I can say because I'm not good at saying things like that”, I found myself nodding in agreement.

    We had gone several kilometers and were almost at my hotel, so I read the last paragraph: “So I thought you'd like to know that I was thinking of you.” And it was ended with “Your Old Friend, Tom.”

    “I thought your friend's name was Ed,” I said.

    “I'm Tom,” he explained. “It's a letter I wrote to Ed before I knew he'd died. I never put it in the mailbox. I guess I should have written it sooner.” His face was pale as he wiped his eyes with a handkerchief.

    When I got to my hotel room I didn't unpack right away. I had to write a letter and post it.

根据短文内容，选择最佳答案，并将选定答案的字母标号填在题前括号内。

    Take a look at the following list of numbers: 4, 8, 5, 3, 7, 9, 6. Read them loud. Now look away and spend 20 seconds memorizing them in order before saying them out loud again. If you speak English, you have about a 50% chance of remembering those perfectly. If you are Chinese, though, you're almost certain to get it right every time. Why is that? Because we most easily memorize whatever we can say or read within a two-second period. And unlike English, the Chinese language allows them to fit all those seven numbers into two seconds.

    That example comes from Stanislas Dahaene's book The Number Sense. As Dahaene explains: Chinese number words are remarkably brief. Most of them can be spoken out in less than one-quarter of a second (for instance, 4 is “si” and 7 “qi”). Their English pronunciations are longer. The memory gap between English and Chinese apparently is entirely due to this difference in length.

    It turns out that there is also a big difference in how number-naming systems in Western and Asian languages are constructed. In English, we say fourteen, sixteen, seventeen, eighteen and nineteen, so one might expect that we would also say oneteen, twoteen, threeteen, and fiveteen.  But we don't. We use a different form: eleven, twelve, thirteen and fifteen. For numbers above 20, we put the “decade” first and the unit number second (twenty-one, twenty-two), while for the teens, we do it the other way around (fourteen, seventeen, eighteen). The number system in English is highly irregular. Not so in China, Japan, and Korea. They have a logical counting system. Eleven is ten-one. Twelve is ten-two. Twenty-four is two-tens-four and so on.

    That difference means that Asian children learn to count much faster than American children. Four-year-old Chinese children can count, on average, to 40. American children at that age can count only to 15. By the age of five, in other words, American children are already a year behind their Asian friends in the most fundamental of math skills.

    The regularity of their number system also means that Asian children can perform basic functions, such as addition, far more easily. Ask an English-speaking seven-year-old to add thirty-seven plus twenty-two in her head, and she has to change the words to numbers (37+22). Only then can she do the math: 2 plus 7 is 9 and 30 and 20 is 50, which makes 59. Ask an Asian child to add three-tens-seven and two-tens-two, and then the necessary equation(等式) is right there, in the sentence. No number translation is necessary: it's five-tens-nine.

When it comes to math, in other words, Asians have a built-in advantage. For years, students from China, South Korea, and Japan — outperformed their Western classmates at mathematics, and the typical assumption is that it has something to do with a kind of Asian talent for math. The differences between the number systems in the East and the West suggest something very different — that being good at math may also be rooted in a group's culture.

    What makes a person a giver or a taker? The idea of “give versus take” takes shape in all relationships of our lives. We're either giving advice, making time for people, or we're on the receiving end. We alternate between the two based on different situations we face on a daily basis, it not an hourly one.

    According to Adam Grant, a professor at Pennsylvania University, most people are matchers. They make careful observations on takers and make it a point for them to pay something back. They hate to see people who act so generously towards others without receiving any reward. Actually, most matchers will try to promote and support givers so that they can get the good they deserve.

    Another professor named Hannah Rile Bowles, from Harvard University, led a study on the idea. She asked 200 senior managers to sit down in pairs where one person would act as the boss and the other as an employee to negotiate salary promotions. Male employees asked for an average salary of $146 k while the females asked for only $141 k. But why did they not bargain as hard as the men? Simply because they were more likely to be givers.

    As a woman, I do enjoy the act of giving up my time, my knowledge and my care and attention to others. I don't expect anything in return, but I do tend to pull myself away when I feel like I'm being taken for granted. I also tend to get upset when I see a loved one's continuous actions of kindness go unnoticed. So it's safe to say I'm 50% giver,35% matcher and 15% taker.

    I do know someone, however, who is 99% giver. They're devoting their time, sharing valuable insights and going out of their way for everyone who crosses their path. Although they've changed the lives of many people, they rarely see any of it returned. But the universe is slowly repaying them; they're now extremely successful, well known for what they do.

    In the United States 30 percent of the adult population has a “weight problem”. To many people, the cause is clear: We eat too much. But scientific evidence does little to support this idea. Going back to the America of 1910, we find that people were thinner than today, yet they ate more food. In those days people worked harder physically（体力地）, walked more, used machines much less, and didn't watch television.

    Several modern studies, moreover, have shown that fatter people don't eat more on average（平均）than thinner people. In fact, some investigations, such as a 1970 study of 3,545 London office workers, report that, on balance, fatter people eat less than slimmer people.

    Studies show that slim people are more active than fat people. A study by a research group at Stanford University School of Medicine found the following interesting facts.

    The more the men ran, the greater loss of body fat.

    The more they ran, the greater their increase in food intake（吸收）.

    Thus those who ran the most ate the most, yet lost greatest amount of body fat.

    Loud cheers and applause broke out at NASA's Jet Propulsion Lab on Monday, November 25, 2018, as the unmanned lander, called Insight, touched down on Mars, after nearly seven years from design to launch to landing.

    The great arrival of the spacecraft­designed to listen for quakes and shakes as a way to discover the Red Planet's inner secrets, how it formed billions of years ago and, how other planets like Earth took shape­marked the eighth successful landing on Mars in Nasa's history.

    Minutes after InSight landed on the surface of Mars, the first image was sent back, showing a wide flat area as seen through a dirty camera.

    The touchdown came after a nearly seven-month, 300 million-mile travel from Earth to Mars, during which the InSight spacecraft had to slow down from a speed of more than 12,000 mph. The spacecraft's heat shelter helped the lander survive temperatures as high as 2,700℉.

    Each step along the way was watched nervously at JPL, with updates delayed by the eight-minute light travel time between Earth and Mars. Mission controllers hugged each other with joy when the signals were received. "We are proud of everything that has gone on today," they told us reporters.

    The first picture of the surface of Mars was sent back to Earth by one of the MarCO nanosatellites (马可纳米卫星) that accompanied InSight during its travel to Mars. The dust from the landing made the view unclear. Pictures from it were expected to be clearer once the dust settled and the lens cover (镜头盖) was removed.

    Hours later, InSight's batteries were charging as expected. The InSight team also passed on another picture, taken by a different camera that's fixed on the lander's robotic arm. The view is clearer, showing the robotic arm and the seismometer, which is used to discover the actual movement of the ground.

Adults check their phones, on average,360 times a day, and spend almost three hours a day on their devices in total. The problem for many of us is that one quick phone-related task leads to a quick check of our emails or social media feeds, and suddenly we've been sucked into endless scrolling.

It's an awful circle. The more useful our phones become, the more we use them. The more we use them, the more we lay neural（神经的） pathways in our brains that lead to pick up our phones for whatever task is at hand-and the more we feel an urge to check our phones even when we don't have to.

What we do know is that the simple distraction of checking a phone or seeing a notification（通知）can have negative consequences. This isn't very surprising; we know that, in general, multitasking does harm to memory and performance. One of the most dangerous examples is phone use while driving. One study found that merely speaking on the phone, not texting, was enough to make drivers slower to react on the road. It's true for everyday tasks that are less high-risk, too. Simply hearing a notification "ding" made participants of another study perform far worse on a task-almost as badly as participants who were speaking or texting on the phone during the task.

It isn't just the use of a phone that has consequences-its me re presence can affect the way we think.

In one recent study, for example, researchers asked participants to either put their phones next to them so they were visible（like on a desk）, nearby and out of sight（like in a bag or pocket）, or in another room. They were found to perform far better when their phones were in another room instead of nearby-whether visible, powered on or not.