Barack Obama was born on August 4, 1961 in Honolulu, Hawaii. His father came to America from Kenya, which is a country in Africa. His parents, Ann and Barack, met when they were students at the University of Hawaii. Since Barack had the same name as his father, young Barack went by the nickname “Barry”.

    In 1979, after he finished high school, Barry went to Occidental College in Los Angeles, California. There, he started to learn about his African roots and decided to use his African name, Barack. After two years in L.A., he went to Columbia University in New York City to study politics.

    After college, he moved to Chicago, Illinois, where he worked to help poor people in his city. He traveled to Africa to meet his grandmother and cousins for the first time. He went back many times over the years to visit with his family and learn about where he came from. At work, he met a lawyer named Michelle Robinson. They worked together in a big law firm. Then he left Chicago to go to Harvard Law School in Cambridge, Massachusetts. He did very well in law school.

    After he was done with school, Barack moved back to Chicago and in 1992 he married Michelle. He worked as a lawyer, devoted to helping poor people for free who had been treated unfairly. He worked hard to get the people he helped to vote.

    He made many people believe that their votes were important, and helped them feel like they could make a difference.

    One of my first memories as a child in the 1950s was a discussion I had with my brother in our tiny bedroom in the family house in Bethlehem, Pennsylvania.

    We had heard in school about a planet called Pluto. It was the farthest, coldest, and darkest thing a child could imagine. We guessed how long it would take to die if we stood on the surface of such a frozen place wearing only the clothes we had on. We tried to figure out how much colder Pluto was than Antarctica, or than the coldest day we had ever experienced in Pennsylvania.

    Pluto, which famously was downgraded from a “major planet” to a “dwarf planet”（矮星） in 2006, captured our imagination because it was a mystery that could complete our picture of what it was like at the most remote corners of our solar system.

    Pluto's underdog discovery story is part of what makes it so attractive. Clyde Tombaugh was a Kansas farm boy who built telescopes out of spare auto parts, old farm equipment and self-ground lenses. As an assistant at Lowell Observatory in Flagstaff, Arizona, Tombaugh's task was to search millions of stars for a moving point of light, a planet that the observatory's founder thought existed beyond the orbit of Neptune. On February 18，1930，Tombaugh found it. Pluto was the first planet discovered by an American, and represented a moment of light in the midst of the Great Depression's dark encroachment (入侵).

    Pluto is much more than something that is not a planet. It's a reminder that there are many worlds out there beyond our own and that the sky isn't the limit at all. We don't know what kinds of fantastic variations on a theme nature is capable of making until we get there to look.

    Being sociable looks like a good way to add years to your life. Relationships with family, friends, neighbors, even pets, will all help, but the biggest longevity (长寿) seems to come from marriage. The effect was first noticed in 1858 by William Farr, who wrote that widows and widowers (鳏夫) were at a much higher risk of dying than the married people. Studies since then suggest that marriage could add as much as seven years to a man's life and two to a woman's. The effect can be seen in all causes of death, whether illness, accident or self-harm.

    Even if the chances are all against you, marriage can more than compensate you. Linda Waite of the University of Chicago has found that a married older man with heart disease can expect to live nearly four years longer than an unmarried man with a healthy heart. Similarly, a married man who smokes more than a pack a day is likely to live as long as a divorced man who doesn't smoke. There's a flip side, however, as partners are more likely to become ill or die in the couple of years following their husband or wife's death, and caring for your husband or wife with mental disorder can leave you with some of the same severe problems. Even so, the chances favor marriage. In a 30-year study of more than 10,000 people, Nicholas Christakis of Harvard Medical School describes how all kinds of social networks have similar effects.

    So how does it work? The effects are complicated, affected by socio-economic factors, health-service provision, emotional support and other more physiological mechanisms(生理机制). For example, social contact can promote development of the brain and immune system, leading to better health and less chance of depression later in life. People in supportive relationships may handle stress better. Then there are the psychological benefits of a supportive partner.

    A life partner, children and good friends are all recommended if you aim to live to 100. The overall social network is still being mapped out, but Christakis says: "People are inter-connected, so their health is inter-connected."

    How can you gain knowledge of the world without books or teachers? Visiting various kinds of world-famous museums may be your best choice. If you are interested ，here are 3 famous museums well worth visiting.
National Gallery, London 2017 attendance: 6,263,000

    The National Gallery originally opened in 1824 in a Pall Mall townhouse with just 38paintings. Today's collection contains over 2, 300 works from the 13th to 19th centuries, which you can appreciate free of charge. The works range in style and time period, but hey, everyone needs to see Van Gogh's Sunflowers in Room 43 at least once, for which the Museum is famous.

    Opening time: daily 10 am—6 pm Friday 10 am—9 pm

    Closed time: January and 24—26 December

    Admission: Free
National Air and Space Museum, Washington, D. C.

    2017 attendance: 7,500,000

    The National Air and Space Museum, part of the Smithsonian Institution, hosts the world's largest collection of aviation and space artifacts. You'll see crowds flocking toward the 1903Wright Flyer and Apollo 11command module, but don't forget about NASA's often—overlooked Stardust probe.

    Hours and Admission :Open every day except December 25.

    Free admission and tickets (free) are needed.

    ⒈A maximum of 4000 free tickets will be issued each day at the museum.

    ⒉Each visitor can once collect one free ticket of the day with valid ID (Passport ).

    Regular Hours :10:00 am to 5:30 pm

    Extended Hours :10:00 am to 7:30pm Fridays, Saturdays and Sundays

National Museum of China, Beijing

    2017 attendance: 7,550,000

    Founded in February 2003, this huge, well-curated museum sits on the edge of Beijing's Tiananmen Square and is free to enter. It houses more than 1.3 million exhibition pieces in its 40halls ，focused primarily on China's achievements in history, culture, and art.

    Opening Hours :9 :00—17:00

    (No Entry after 16:00) Closed on Mondays

    Museum Visiting Tips: Limit the number of bags( only one handbag is allowed ). All visitors are screened through metal detector upon entry. The fewer items you bring inside the Museum. Before you visit, please review the list of prohibited items, Visitors carrying prohibited items will not be allowed inside the Museum, s0 please leave them at home or in your car.

    No Food or Drink: Only bottled water is permitted in the Museum

    To help you travel well in Argentina, we've put together some exciting activities, courses and tours that you can add to your schedule. These are not only designed to be fun, but also to enable you to learn and expand your personal and professional development.

    Walking Tour of La Boca

    The 5-hour tour, moderate（适度的）walking, departs at 11 am in Monserrat and finishes at 4:30 pm, Tuesdays and Fridays.

    Price: £15 per person

    Tour the beautiful cobble stone（鹅卵石）streets of Le Boca, the heart of Buenos Aires and the birth place of Tango. This fascinating walking tour is a must if you want to explore the rich history of Buenos Aires.

    Photography Courses

    6 hours of lessons per week

    Price: £295 for two weeks

    Study photography with an experienced private tutor who will tailor your lessons to your individual needs. Classes include practical teaching, analysis of your work, theory and history and regular opportunities to explore the city by yourself to photograph landscapes of the city.

    Graffiti Tour of Buenos Aires

    The 3-hour tour departs at 3 pm in Colegiales and finishes at 6 pm in Palermo, Wednesdays, Thursdays, Fridays or Saturdays.

    Price: £35 per person

    Experience the world of urban art through this wonderful tour of Buenos Aires. You can travel both on foot and by air-conditioned minibus. The tour finishes in Post Bar in Palermo, home to the unique street art gallery Hollywood and Cambodia.

    Spanish Courses

    1-Week Intensive Course with private lessons, before starting your Main Project

    Price: £590 per week

    Weekly Lessons: 10 hours of lessons per week running concurrent with your Main Project

    Price: £195 per week

    Use your time in Argentina to learn Spanish. You can either do a 1 -week intensive course or take lessons at the same time as doing your main project.

    Robots make me nervous—especially the ones which seem to think for themselves. I was embarrassed to admit this till I heard that Bill Gates, the founder of Microsoft, felt the same way.

    Gates said in an interview with the social networking and news website Reddit: "I am in the camp that is concerned about super intelligence. First the machines will do a lot of jobs for us and not be super intelligent．That should be positive if we manage well. A few decades after that, though, the intelligence is strong enough to be a concern."

    Well, maybe I don't have to worry about my computer and kitchen equipment yet. After I use them I can always pull the plug. But in the future, machines might find a way to prevent us from switching them off. There's a terrible thought!

    Maybe the problem with computers too clever for us is not that they are evil like some we've seen in sci-fi movies. What could put us in danger is that they might be too efficient. That's what philosopher Nick Bostrom from Oxford University believes. He says that machines are indifferent to humans and in pursuit of their own goals，the destruction of people might be just additional damage. Bostrom gives us an example: A machine which might have its only goal to produce as many paperclips as possible might look at human bodies as extra material for paperclips and go after you. Because it is, well, a machine, it would not take pity on you.

    It's a good thing that American writer Isaac Asimov thought about how far robots can go and left us his three rules of robotics. They state that a robot may not hurt a human being or allow the human being to come to harm.

    I'm glad my machines at home are "dumb". All my cleaner wants to take over is the carpet in my living room. Let's hope they don't create an appliance which wants to take over the world!