This year's flu season is pretty scary. To try to minimize the effects, public officials are still urging anyone who hasn't yet gotten their flu shot to get one as soon as possible. However, even if every single person got a shot in the arm, the vaccine(疫苗)— with its excellent 36 percent effectiveness—would not prevent everyone from getting infected with the annoying virus. Knowledge is power, so here's what goes on in your body when you come down with the flu.

    The influenza virus primarily attacks your nose, throat, and the tubes that lead to your lungs. But the flu is so much more than that. Your muscles ache, your head hurts, and your appetite goes down, among other things. To our surprise, almost all of these symptoms have less to do with the virus itself than with your immune(免疫的)response to them. Unfortunately, the very defense you have in place to ge rid of the flu is the reason you feel so painful when you recover.

    The virus usually enters through your mouth, typically by way of your hands. But it takes a few days for symptoms to set in. While this process might cause some harm to your nose and throat, it's nothing major, and nothing like the symptoms that typically accompany a bad or even mild case of the flu.

    The real fun starts when your immune system begins to fight. Your immune system comes in two parts: the innate system and the adaptive. The innate immune system is essentially an all-purpose tool. As soon as your body senses the presence of any injury or invader (入侵者), the innate immune system launches into action by producing tiny proteins called cytokines and chemokines. The cytokines reproduce almost immediately and start to attack the virus. This increase in immune cells creates an serious inflammation(炎症) throughout the body. But the worst is still to come. Meanwhile, the chemokines work with the adaptive immune system to help create T cells. These cells are a special type of white blood cell that works in a much more specific way: They find the influenza virus, identify what's special about it, and create something unique on their surface that finds and destroys similar invaders.

    One night about nine o'clock, Dr. Eyck, a surgeon, had a phone call from Dr. Haydon at the hospital in Clens Falls. The surgeon was asked to go there at once to operate on a very sick boy who shot himself while playing with a gun.

    The doctor was soon on his way to Clens Falls. It was 60 miles away. And it was snowing heavily in the city. The surgeon thought he could get there before 12 o'clock.

    A few minutes later, the doctor was stopped by a man in an old black coat. Gun in hand, the man ordered the doctor to get out. Then the man drove the car down the road, leaving the doctor in the falling snow.

    It was after 2 o'clock in the morning when the doctor arrived at the hospital in Clens Falls. Dr. Haydon told him that the boy had died an hour before. The two doctors walked by the door of the hospital waiting room. There sat the man in the old black coat with his head in his hands“Mr. Cuninghan,”said Dr. Haydon to the man, “This is Dr. Eyck. He is the surgeon who walked all the way from Albany to save your boy.”

    For high school leavers starting out in the working world, it is very important to learn particular skills and practise how to behave in an interview or how to find all internship(实习). In some countries, schools have programs to help students onto the path to work. In the United States, however, such programs are still few and far between.

    Research shows that if high schools provide career-related courses, students are likely to get higher earnings in later years. The students are more likely to stay in school, graduate and go on to higher education.

    In Germany, students as young as 13 and 14 are expected to do internships. German companies work with schools to make sure that young people get the education they need for future employment.

    But in America, education reform programs focus on how well students do in exams instead of bringing them into contact with the working world. Harvard Education school professor Robert Schwartz has criticized education reformers for trying to place all graduates directly on the four-year college track. Schwartz argued that this approach leaves the country's most vulnerable(易受影响的) kids with no jobs and no skills.

    Schwartz believed that the best career programs encourage kids to go for higher education while also teaching them valuable practical skills at high school. James Madison High School in New York, for example, encourages students to choose classes on career-based courses. The school then helps them gain on-the-job experience in those fields while they're still at high school.

    However, even for teens whose schools encourage them to connect with work, the job market is daunting. In the US， unemployment rates for 16-to-l9-year-olds are above 20 percent for the third summer in a row.

    “The risk is that if teenagers miss out on the summer job experience, they become part of this generation of teens who had trouble in landing a job,” said Michael, a researcher in the US.

    The origin of “holiday” is easy to see, coming from “holy day”, a day of particular religious significance, often celebrating the life of a saint (圣徒), during which no work was to be done. As far back as the 11th century, “holidays”, especially the major feast days, were times of “celebration and amusement”, as the Oxford English Dictionary puts it.

    The number of holidays steadily increased during the Middle Ages, until a medieval Englishman would have had the luxury of 40 to 50 days a year off work, depending on where he lived, in addition to a free day on Sundays.

    During the Reformation, Henry VIII abolished most of the holidays partly because of the Protestant (新教徒的) suspicion of saints, but more practically, because, according to historian Eamon Duffy, “A large number of holidays were making the people poor by limiting agriculture.” The people took a different view and organized a protest march—the Pilgrimage of Grace—partly to protect their days off.

    Though at first the religious and festive senses of holiday were combined, the word gradually came to be used for any kind of relaxing break from work. As the word was drawing away from a religious society, the number of authorized holidays was reduced, until by 1834 most workers had only four official days off a year, in addition to Sundays. Many factory workers amplified this time by staying home on “Saint Monday” to recover from what they had gotten up to the day before.

    By the late 19th century, employers were compromising and offering half-day Saturdays, the beginning of the “weekend”, a term first used in 1879. In 1908, an innovative mill in New England gave its employees all of Saturday off, and the practice spread widely during the Great Depression as a way to keep employment up. It took 400 years, but finally workers could enjoy as many holidays as they had in the 15th century.

    Let children learn to judge their own work. A child learning to talk does not learn by being corrected all the time; if corrected too much, he will stop talking. He notices a thousand times a day the difference between the language he uses and the language those around him use. Bit by bit, he makes the necessary changes to make his language like other people's. In the same way, children learn to do all the other things without being taught to walk, run, climb, whistle, ride a bicycle…They compare their own performances with those of more skilled people, and slowly make the needed changes. But in school we never give a child a chance to find out his mistakes and correct them for himself. We do it all for him. We act as if we thought that he would never notice a mistake. If it is a matter in mathematics or science, give him the answer book. Let him correct his own papers. Why should we teachers waste time in such routine(日常的) work? Our job should be to help the child when he tells us that he can't find the way to get the right answer. Let the children learn what all educated persons must some day learn, how to measure their own understanding, how to know what he does not know.

    FaceApp has taken the world by storm, giving users the chance to see themselves age through its algorithm. 12.7 million people—some three million more than the population of New York City—reportedly downloaded it in one seven-day period last month.

    Although the Russian app has become known for its privacy issues, the more interesting lesson of our FaceApp fling (尽情玩乐)is what it tells us about our society—and our future lives. It turns out we are more interested in aging than we realized. I'm surprised by this. Most younger people are in denial (否认)about old age, doing almost nothing to prepare for it. We rarely have a chance to plan for the future, with increasing time and financial pressures. Those pressures bring sacrifices that we may not always want to make: we can no longer afford to spend the time or the money needed to look after our elderly parents.

    As a family doctor, I can see the loneliness epidemic developing. Elderly patients come to see me with no particular illness, no clear medical issue. After a few minutes of the consultation, I understand why: they're not sick, and often they don't feel sick. They just need someone—anyone-to talk to.

    Although loneliness has no medical classification, the health effects are real: the result of loneliness and isolation can be as harmful to our health as smoking 15 cigarettes a day, and is more damaging than obesity. But loneliness does not come with nearly enough health warnings.

    So what next? Since 1980, we are living on average 10 years longer. At the same time, people are having fewer and fewer children, and they are having them much later in life. The snake of a world class health service is eating its own tail; its care is prolonging (延长) people's lives, but as the ratio of pensioners(退休人员)to working -age people increases, there are fewer taxpayers to fund that very health service.

    Into this void have stepped NGOs, charities and volunteers. But in the long term, the only way to truly help the oldest meters of our society is to go back to the traditional values of intergenerational(两代间的) cooperation—often under same roof. Ultimately, we will need to evolve towards a culture where elderly care is treated the same as childcare, where employers recognize the duty of someone with an elderly parent the same way they recognize those of someone with a newborn child.