After suffering through many months of unemployment  (失业). my wife and I moved this week from Colorado to Ohio. where she was starting a new job. Not knowing anybody there. we were pretty concerned about how we'd get our entire home unloaded (卸下) without killing ourselves.

    We made a phone call to hire (临时雇用) a couple of college students to help with all the heavy lifting once we got there. But one neighbor after another stopped by to help us. What ? Have we moved to some other country ? Maybe we've died and gone to heaven!     

    Unloading actually became fun and joy because there were so many wonderful new friends to help when we worked. The more people helped. the easier the work became. We were afraid the job might take days for the two of us alone. but it was finished in a few hours. Many total strangers would either walk by the sidewalk or drive by to ask us if we were moving in. Many were happy that this old house that had sat empty for so long was coming to life again. We were invited to an outdoor meal yesterday by neighbors on the same street.

    All the time. my brain was resting on this new sense of hope that people can be so friendly to strangers. Among all the conversation were lots of offers to help each other in all kinds of ways. It's wonderful to live in such a kind little town. I feel so grateful to be here. and wish the rest of the world could see how an entire community can model  (做榜样) what it's like to help each other.

    A family is a collection of people who share the same genes（基因）but cannot agree on a place to pull over for lunch. Ed and I, plus his parents and sister Doris and eight-year-old niece Alisha, are on a road trip to Yosemite. Ed wants Subway, I want. In-N-Out Burger, Doris wants Sonic. In the end, we compromise on McDonald's, where Alisha will get an action figure.

    It's a three-hour drive to Yosemite, but we're taking a little longer, as we're working in a tour of Highway 80's public restrooms. As the saying goes, “Not one bladder（膀胱）empties but another fills.” Many of these restrooms belong to gas stations. I prefer them to the high-tech ones on planes.

    We get back on the road. Ed is driving now. When all the tabloids（小报）have been read, the travel has grown tedious and anyone under age 12 asks “Are we there yet?” at ever-shortening internals. Just outside Manteca, California, we stop for coffee. At a Starbucks checkout, Ed buys a CD of Joni Mitchell's favorite musical picks. The hope is that it will have a calming effect.

    As we pull back onto the highway, it starts to pour. Then something amazing happens. As we climb the mountain, the rain turns to snow. The pines are spotted with white. We're struck dumb（说不出话）by the scene outside. For a solid 15 minutes, everyone forgets about their bladder, their blood sugar and the temperature. Alisha has never seen snow, so we pull over to make snowmen and catch snowflakes on our tongues. Then Ed realizes we need tire chains, and we have to turn back and drive 30miles to Oakhurst. “Good,” says Doris. “There was a very nice restroom there.”

Hollywood's theory that machines with evil(邪恶) minds will drive armies of killer robots is just silly. The real problem relates to the possibility that artificial intelligence(AI) may become extremely good at achieving something other than what we really want. In 1960 a well-known mathematician Norbert Wiener, who founded the field of cybernetics（控制论）, put it this way: “If we use, to achieve our purposes, a mechanical agency with whose operation we cannot effectively interfere(干预), we had better be quite sure that the purpose put into the machine is the purpose which we really desire.”

A machine with a specific purpose has another quality, one that we usually associate with living things: a wish to preserve its own existence. For the machine, this quality is not in-born, nor is it something introduced by humans; it is a logical consequence of the simple fact that the machine cannot achieve its original purpose if it is dead. So if we send out a robot with the single instruction of fetching coffee, it will have a strong desire to secure success by disabling its own off switch or even killing anyone who might interfere with its task. If we are not careful, then, we could face a kind of global chess match against very determined, super intelligent machines whose objectives conflict with our own, with the real world as the chessboard.

The possibility of entering into and losing such a match should concentrate the minds of computer scientists. Some researchers argue that we can seal the machines inside a kind of firewall, using them to answer difficult questions but never allowing them to affect the real world. Unfortunately, that plan seems unlikely to work: we have yet to invent a firewall that is secure against ordinary humans, let alone super intelligent machines.

Solving the safety problem well enough to move forward in AI seems to be possible but not easy. There are probably decades in which to plan for the arrival of super intelligent machines. But the problem should not be dismissed out of hand, as it has been by some AI researchers. Some argue that humans and machines can coexist as long as they work in teams—yet that is not possible unless machines share the goals of humans. Others say we can just “switch them off” as if super intelligent machines are too stupid to think of that possibility. Still others think that super intelligent AI will never happen. On September 11, 1933, famous physicist Ernest Rutherford stated, with confidence, “Anyone who expects a source of power in the transformation of these atoms is talking moonshine.” However, on September 12, 1933, physicist Leo Szilard invented the neutron-induced(中子诱导) nuclear chain reaction.

    Crossing your legs is an extremely common habit; most people don't even notice that they're doing it when they sit down. While you may find it comfortable to sit with one knee crossed over the other, it might be causing health problems that you are not aware of.

    A study published in Blood Pressure Monitoring stated that sitting with your legs crossed can increase your blood pressure. The reason for this is that the blood in your legs has to work against gravity to be pumped back to your heart and that crossing one leg over the other increases resistance(阻力), making it even harder for the blood to circulate. This causes your body to increase your blood pressure to push the blood back to the heart. You won't feel any immediate effects, but repeated, drawn-out increases in blood pressure can cause long-term health problems. So, planning to sit for a long period of time? Don't keep your legs crossed.

    Crossing your legs at the knee can also cause pressure on the major nerve in your leg that passes just below your knee and along the outside of your leg, explains Richard Graves, a medical expert. This pressure can cause numbness and temporary paralysis (麻痹) of some of the muscles in your foot and leg, preventing you from being able to raise your ankle—what we know as that “pins and needles” sensation. While the feeling of discomfort may only last a minute or two, repeatedly crossing your legs until they feel numb can cause permanent nerve damage.

    So next time you sit down, try to get yourself in the habit of sitting with both of your feet on the floor. Not only will it help your posture and stability, but it will also save your health in the long run.

    Since so much written language we see today comes from a glowing screen, language has begun to change through our interaction with technology. Social media and the Internet have had a rapid and great effect on the English language, and not necessarily for the better. More and more people have found themselves writing in pieces of words and using unclear acronyms(单词首字母) both in written and spoken language.

    How many times have you typed "LOL" in response to a humorous message? Referred to someone as your "BFF"? Exclaimed, "OMG!" during a particularly shocking event? Social media has affected the words we use in our everyday life. Abbreviations and acronyms commonly known as "text talk" have made their way into both spoken and written language. These are becoming increasingly popular as people struggle for brief expressions to meet word limits on social media like Weibo and Twitter. In addition, the speed of the Internet means language is changing faster than ever. You no longer have to be published through physical and traditional means to bring word trends to public attention.

    Many people believe the overuse of these new terms is a passing trend, and nobody will be using them in just a couple of decades. With the change of language, older terms will surely disappear and fall out of style, and newer and more Internet language will take their place.

    But the Oxford English Dictionary thinks the contrary. In 2011, a lot of Internet terms including, "LOL," "BPB," "OMD," and "BFF" were added to the dictionary, making these acronyms official parts of the English language. According to the dictionary writers, these terms aren't going anywhere anytime soon.

    The words you use in everyday life are a reflection of yourself; this is especially true on the Internet with the lack of interaction in real life. With the Internet and social media rapidly getting popular, soon your words may be all you have left. Make them good ones.

    Fire fighting is a serious matter. Knowing what to do during a fire can save people's lives. It is important to know the ways you can use and show them to everyone else in the family, such as stairways and emergency exits, but not elevators.

    From the lower floors of buildings, escape through windows is possible. Learn the best way to get out from a window with the least chance of serious injury.

    The second floor window is usually not very high from the ground. An average person, hanging by the fingertips will have a drop of about 6 feet to the ground. It is about the height of an average man. Of course, it is safer to jump a short way down than to stay in a burning building.

    Windows are also useful when you are waiting for help. Be sure to keep the door closed before opening the window. Otherwise, smoke and fire may be drawn into the room. Keep your head low at the window to be sure you get fresh air rather than smoke that may have leaked(漏)into the room.

    On the second or third floor, the best windows for escape are those which open onto a roof. From the roof a person can drop to the ground more safely. Dropping onto cement might end in injury. Bushes and trees can help you to have a soft landing.