A new international study shows that some people's biological clock plays a powerful role for their life expectancy, regardless of lifestyle choices.

    Published in the latest issue of Aging on Wednesday, the study has found the most definitive evidence to explain why some people keep healthy lifestyle but die younger than others.

    Geneticist Steve Horvath from the University of California, Los Angeles (UCLA), led a team of 65 scientists around the world to record age-related changes to human DNA, analyse blood samples collected from 13, 000 people and estimate their lifespan.

    A higher biological age, regardless of actual age, consistently predicts an earlier death, the study says.

    "You get people who are vegan, sleep 10 hours a day, have a low-stress job, and still end up dying young," Horvath said in a statement. "We have shown some people have a faster innate aging rate."

    The findings discovered that 5 percent of the population ages at a faster biological rate, which translated to a roughly 50 percent higher than average risk of death at any age.

    "The great hope is that we find anti-aging interventions that would slow your innate aging rate," Horvath said, adding that "this is an important milestone to realizing this dream."

    No one is sure how many Americans belong to reading groups called book clubs. Yet{#blank#}1{#/blank#} (publisher) and bookstores report that more and more people throughout the United States are joining{#blank#}2{#/blank#} (they).

    Most of the clubs work the same way. Members read the same book at the same time. Then they meet to talk about the book. Members may be friends or people{#blank#}3{#/blank#} live near each other. Some Americans belong to reading groups on{#blank#}4{#/blank#}Internet. These groups include people around the world who communicate about books they read. They send electronic mails instead of gathering{#blank#}5{#/blank#} (discuss) books.

    Most reading groups study books by{#blank#}6{#/blank#} (variety) writers. However, some groups read the work of a single writer,{#blank#}7{#/blank#} (usual) one that has been famous for a while. Other groups may{#blank#}8{#/blank#} (name) for an important person in the work of the writer,{#blank#}9{#/blank#} a Sherlock Holmes Club. Members of these book clubs often are experts about their{#blank#}10{#/blank#} (choose) reading materials. One member of a Holmes reading group, for example, can identify almost every person in every Sherlock Holmes story.

    I always wondered how people would react if I tried to approach a total stranger for help in a busy place like a street corner or in a noisy mall. I have always hurried past a stranger who tried to catch my attention in a busy place or when I am rushing around.

    Yesterday, I was in a busy shopping mall buying a large piece of luggage because I just had the time to do it after many days of planning. After the purchase in one of the large shops, I picked up my phone from my pocket to call my driver waiting in the parking lot but my phone was dead.

    I then requested the shop assistant who had just sold me the luggage to ring the number of my driver for me and she replied that it was the shop policy that they cannot use mobile phones while working in the shop.

    I got out of the shop onto the busy street in front and approached a young mother with her two kids to make a request. As soon as I said “Excuse me, madam”, she grabbed both her kids and ran. I felt like a kidnapper.

    I stood there, wondering how many times I had reacted to strangers like the young mum. I stood there in the busy street with people rushing by, looking at their faces to see if there was a sign of kindness on their faces.

    I saw a man pretty shabbily dressed. He seemed to have noticed me and I just stopped him expecting him to rush past. My request escaped the lips. He immediately called the number of my driver and waited till my car came to be sure I was picked up, and he turned around before I could thank him adequately and was gone. I was surprised by his kindness and hope I will do likewise (同样地) to strangers who try to catch my attention from now on.

    Many people spend more than four hours per day on We Chat, and it is redefining the word “friend.” Does friending someone on social media make him or her your friend in real life?

    Robin Dunbar, a professor at Oxford University, found that only 15, of the 150 Facebook friends the average user has, could be counted as actual friends and only five as close friends. We Chat may show a similar pattern.

    Those with whom you attended a course together, applied for the same part-time job, went to a party and intended to cooperate but failed take up most of your WeChat friends. In chat records, the only message may be a system notice, “You have accepted somebody's friend request”. Sometimes when seeing some photos shared on “Moments”, you even need several minutes to think about when you became friends. Also, you may be disturbed by mass messages (群发信息) sent from your unfamiliar “friends”, including requests for voting for their children or friends, links from Pinduoduo.com (a Chinese e-commerce platform that allows users to buy items at lower prices if they purchase in groups) and cookie-cutter (千篇一律的) blessings in holidays.

    You would have thought about deleting this type of “friends” and sort out your connections. But actually you did not do that as you were taught that social networking is valuable to one's success. Besides, it would be really awkward if they found that you have unfriended them already. Then, you keep increasing your “friends” in social media and click “like” on some pictures that you are not really interested. But the fact is that deep emotional connections do not come with the increasing number of your friends in social media.

    If the number of your friends reaches 150, maintaining these relationships can be tough to you, and sometimes even will make you anxious. According to Robin Dunbar, 150 is the limit of the number of people with whom one can maintain stable social relationships.

    Johnny Smith was a good math student at a high school. He loved his computer. He came home early every day, then he worked with it till midnight. But Johnny was not a good English student, not good at all. He got an F in his English class.

    One day after school Johnny joined his computer to the computer in his high school office. The school office computer had the grades of all the students: the math grades, the science grades, the grades in arts and music, and the grades in English. He found his English grade. An F! Johnny changed his English grade from an F to A. Johnny' parents looked at his report card. They were very happy.   "An A in English!" said Johnny's Dad. "You're a very clever boy, Johnny." Johnny is a hacker.

    Hackers know how to take information from other computers and put new information in. Using a modem, they join their computers to other computers secretly. School headmasters and teachers are worried about hackers. So are the police, for some people even take money from bank computer account and put it into their own ones. And they never have to leave home to do it! They are called hackers.