When asked about happiness, we usually think of something extraordinary, an absolute delight, which seems to get rarer as we get older.

    For kids, happiness has a magical quality: Their delight at winning a race or getting a new bike is unreserved (毫不掩饰的).

    In the teenage years, the concept of happiness changes. Suddenly it's conditional on such things as excitement, love and popularity. I can still recall the excitement of being invited to dance with the most attractive boy at the school party.

    In adulthood the things that bring deep joy－love, marriage, birth－also bring responsibility and the risk of loss. For adults, happiness is complicated (复杂的).

    My definition of happiness is “the capacity for enjoyment”. The more we can enjoy what we have, the happier we are. It's easy to overlook(忽视) the pleasure we get from the company of friends, the freedom to live where we please, and even good health.

    I experienced my little moments of pleasure yesterday. First I was overjoyed when I shut the last lunchbox and had the house to myself. Then I spent an uninterrupted morning writing, which I love. When the kids and my husband came home, I enjoyed their noise after the quiet of the day.

    Psychologists tell us that to be happy we need a mix of enjoyable leisure time and satisfying work. I don't think that my grandmother, who raised 14 children，had much of either. She did have a network of close friends and family, and maybe this is what satisfied her most.

    We, however, with so many choices and such pressure to succeed in every area, have turned happiness into one more thing we've got to have. We're so self-conscious about our “right” to it that it's making us miserable. So we chase it and equal it with wealth and success, without noticing that the people who have those things aren't necessarily happier.

    Happiness isn't about what happens to us－it's about how we see what happens to us. It's the skillful way of finding a positive for every negative. It's not wishing for what we don't have, but enjoying what we do possess.

    We brush our teeth daily, but do you know everything you need to know about dental care and hygiene? Believe it or not, there is a lot more than most people realize. Luckily, here are several apps that can help you.

●Brush DJ

    You should brush your teeth for full two minutes as recommended by dentists, but that time can be difficult to judge. Many recommend you listen to music, because many songs are just around two minutes in length. Brush DJ has loads of great tunes that will get you into the two­minute habit. There are both songs to listen to, and videos to watch, and you'll find a variety of awesome tunes.

●Orasphere

    It's recommended that Orasphere videos be used by dentists for their patients, so they can learn about procedures. Those who do use these videos say that the software can greatly decrease the amount of time it takes to explain procedures to patients.

●American Dental Association(ADA)

    Everything you ever wanted to know about your teeth, and then some, can be found on the American Dental Association(ADA) website. You'll find loads of great articles that have the latest news about dentistry（牙科）. Those interested in dental careers will find plenty of information to head them in the right direction, and there's even a section devoted to public dental programs, including Give Kids a Smile and Fluoride in Water.

●DDS GP

    Here is more presentation software that explains all types of dental procedures. This is helpful for dentists to have, because they can better explain procedures to their patients.

●Dentistry IQ

    You can find information for dentists, hygienists, assistants, office managers, and more at Dentistry IQ. You can also get information about new products, clinical practices, and much more. In addition, you can learn about career opportunities, the most recent practices, and a whole lot more.

    A new phone app uses shaking from smartphones to warn people about earthquakes. The new app is called MyShake, which is the work of four researchers at the University of California. Berkeley.

    Smartphones are equipped with accelerometers(加速器). MyShake uses phone accelerometers to measure seismic (地震的) activity. It has been programmed to know the difference between normal activity and earthquake movement. The software developers say their app is right 93 percent of the time. A smartphone sends seismic information to the app developers. If the developers receive several warnings from one area, it recognizes that an earthquake may be taking place or will take place soon. Using information sent from the app, the network then judges the location and strength of the quake in real time. MyShake can record 5.0 earthquake at distances of 10 kilometers or less.

    MyShake uses very little power, according to its developers. Only when seismic activity is sensed by the app does it become active and sends data to the network. The app works best when your phone is resting on a flat surface, like a table.

    The developers hope that MyShake can add to information collected by the U.S Geological Survey. That U.S agency has created the Earthquake Early Warning System, also known as the EEW. The EEW has used sensors for measuring quakes in many areas. In places where no such equipment exists, MyShake may be the only method of early quake detection (发现). The app also shows ways to stay safer during an earthquake. The developers say it will become more effective as more people use it.

    The developers say they hope to add a feature that will warn people about possible tsunami after an earthquake.

    It's 8 a.m., Tuesday, Nov. 18, 2028, and you are headed for a business appointment 300 miles away. You step into your circle, two­passenger air­cushion car, press a series of buttons and the national traffic computer notes your destination, figures out the current traffic situation and signals your car to slide out of the garage. Hands free, you sit back and begin to read the morning paper — which is flashed on a flat TV screen over the car's dashboard. Tapping a button changes the page.

    The car speeds up to 150 mph in the city's countryside, and then hits 250 mph in less built­up areas, driving over the smooth plastic road. You fly past a string of cities, many of them covered by the new domes (圆屋顶) that keep them evenly climatized all year round. Traffic is heavy, typically, but there's no need to worry. The traffic computer, which sends and receives signals to and from all cars on the road between cities, keeps vehicles at least 50 yds apart. There hasn't been an accident since the system began.

    Suddenly your TV phone buzzes. A business partner wants a sketch of a new kind of impeller your firm is putting out for sports boats. You reach for your case and draw the diagram with a pencil­thin infrared flashlight (红外线闪光灯) on what looks like a TV screen lining the back of the case. The diagram is sent to a similar screen in your partner's office, 200 miles away. He presses a button and a fixed copy of the sketch rolls out of the machine. He wishes you good luck at the coming meeting and signs off.

    Ninety minutes after leaving your home, you slide beneath the dome of your destination city. Your car slows down and heads for an outer­core office building where you'll meet your colleagues. After you get out, the vehicle parks itself in a garage to await your return. Private cars aren't allowed inside most city cores. Moving sidewalks and electrams (电车) carry the public from one location to another.

    Charlie is a teacher and his wife, Maria is an artist. The night before last, just before the longest day of the year, Charlie was sitting in a deckchair enjoying the warm summer air when Maria touched his shoulder and he could tell immediately she was a little worried about something. He asked her what the matter was and she replied that there was a strange thing on the jacket that was hanging in the bedroom. They had both lived in the West Indies (西印度群岛) and had seen a lot of strange creatures in their house before. But now they were living in England and so Charlie just laughed and said he would have a look at the "thing".

    He walked to the bedroom. He saw a jacket hanging in the bedroom and went up to it to have a closer look at the "thing". The moment he touched it, the thing sprang into life. Now Charlie experiences fear like the rest of us but when this creature opened its wings, he jumped out of his skin and ran screaming from the room like a small child doing about 100 miles an hour.

    For a moment the next-door neighbours thought that Charlie was murdering his wife because of the noise they could hear. In fact, it was a bat that frightened Charlie.

    Eventually Charlie managed to trap the bat in a box and took it to the garden to let the bat fly. Maria, who had been playing the guitar while Charlie was upstairs, asked Charlie if he had found out what the thing was. "Oh, nothing to worry about", he said casually hoping that the terror could not be seen in his eyes, "it was just a bat."