More than 10 years ago, it was difficult to buy a tasty pineapple.The fruits that made it to the UK were green on the outside and, more often than not,hard with an unpleasant taste within.Then in 1966,the Del Monte Gold pineapple produced in Hawaii first hit our shelves.

    The new type of pineapple looked more yellowy-gold than green.It was slightly softer on the outside and had a lot of juice inside.But the most important thing about this new type of pineapple was that it was twice as sweet as the hit-and-miss pineapples we had known. In no time, the Del Monte Gold took the market by storm, rapidly becoming the world's best-selling pineapple variety, and delivering natural levels of sweetness in the mouth,up until then only found in tinned pineapple.

    In nutrition it was all good news too.This nice tasting pineapple contained four times more vitamin C than the old green variety.Nutritionists said that it was not only full of vitamins, but also good against some diseases.People were understandably eager to be able to buy this wonderful fruit.The new type of pineapple was selling fast9 and the Del Monte Gold pineapple rapidly became a fixture in the shopping basket of the healthy eater.

    Seeing the growing market for its winning pineapple, Del Monte tried to keep market to itself.But other fruit companies developed similar pineapples.Del Monte turned to law for help, but failed. Those companies argued successfully that Del Monte's attempts to keep the golden pineapple for itself were just a way to knock them out the market.

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    How fit are your teeth? Are you lazy about brushing them? Never fear: An inventor is on the case. An electric toothbrush senses how long and how well you brush, and it lets you track your performance on your phone.

    The Kolibree toothbrush was exhibited at the International Consumer Electronics Show in Las Vegas this week. It senses how it is moved and can send the information to an Android phone or iPhone via a Bluetooth wireless connection.

    The toothbrush will be able to teach you to brush right (don't forget the insides of the teeth!) and make sure you're brushing long enough. “It's kind of like having a dentist actually watch your brushing on a day-to-day basis,” says Thomas Serval, the French inventor.

    The toothbrush will also be able to talk to other applications on your phone, so developers could, for instance, create a game controlled by your toothbrush. You could score points for beating monsters among your teeth. “We try to make it smart but also  fun,” Several says.

    Serval says he was inspired by his experience as a father. He would come home from work and ask his kids if they had brushed their teeth. They said “yes,” but Serval would find their toothbrush heads dry. He decided he needed a brush that really told him how well his children brushed.

    The company says the Kolibree will go on sale this summer, for $99 to $199, developing on features. The U.S. is the first target market.

    Serval says that one day, it'll be possible to replace the brush on the handle with a brushing unit that also has a camera. The camera can even examine holes in your teeth while you brush.

    Recently I started discovering one thing which amazes me so much: how perfect everything is in the world we are living in! Just look, all day long we are busy working and just when we get tired, the night comes in, so we may sleep and relax. One day we may enjoy the bright sun and another day, when we get tired of the sun, the rain pours down.

    A few months ago I was so happy with my life. Later, I got tired from the happiness. I wished I would have some trial to strengthen my character and learn something new about life. I got what I wanted. Shortly after I got severe angina (心绞痛), so I had to stay home for several weeks. During this period I had time to rethink my life and discover myself. The lessons were terrific, but I felt grateful for this time.

    Another example: I have a friend, who primarily thinks about having fun. Once I thought why we get along well with each other and what in me attracts her. A couple of days ago I found the answer. I like calmness and silence. She likes noise and agitation (热闹). We attract each other just to balance ourselves, in other words, to give some drive to me and some calmness to her!

    So remember that the universe is so wise that it will try to balance you. As for me, this is perfect because extremes create suffering: too much food – too little food, too cold – too hot, too much fun – too little fun.

    For many, music is as important to the human experience as eating and breathing. We hear music everywhere—at home, the gym, parties and stores. But what kind of music do we prefer to listen to, and when and why do our musical preferences change?

    The relationship between the change of seasons and musical preferences was the focus of a study led by psychologist Terry Pettijohn. He and his team based their research on a previous study that examined the relationship between popular music preferences and the Environmental Security Hypothesis(假设). The results showed that over time, when social and financial conditions were more risky, the songs of the year that were slower, longer, more comforting and serious were most popular. And during periods in which social and financial conditions were generally stable, the result was opposite.

    Building on these findings, Pettijohn and his team wondered if the Hypothesis could also be applied to the change of seasons. For college students, the participants in this study, autumn begins at the start of the school year. Gone are the carefree days of summer, when school is out. Winter means colder temperatures, shorter days, and, in many places in the country, snow. Spring, however, is a different story. It represents a fresh start and when clocks spring forward, we gain an extra hour of daylight. As students walk into summer, they're absorbed in the sunshine and social activities—and enjoy a break from school.

    But do changing seasonal conditions influence musical preferences? To answer this question, the researchers designed two studies. What did they find? Both groups of college students favored more serious music during the seasons of fall and winter, and more active and energetic music during the spring and summer seasons. And these findings, Pettijohn argues, have practical significances.

FITNESS CENTRE

    The fitness centre offers a variety of activities for members of all ages throughout the week.

    Activities for Monday 12 July, 2017:

    Learn to swim. Classes for preschool children aged five and under start at 10:00 am. Classes last 30 minutes and parents must attend with their children. Don't forget to book in advance, as places are limited, and to pack some warm clothes for after the lesson.

    Woman's aerobics (有氧运动). Sessions are for one hour and begin at 10:45 am, led by Melissa. Come along and join us every Monday for an exhilarating hour of exercise and fun. Leave your kids at the nursery and take time out for yourself. Wear a track­suit or something similar.

    Lunchtime yoga. Take a break at lunchtime (1:00—2:00 pm) for an hour of meditation and yoga. Enjoy the peace and quiet of our meditation room, and relaxing sessions designed for active people with busy lives. Use your own mat for floor work or hire one from us for a small sum.

    Family Shootaround. 10:00—5:30 pm. Family Shootaround is open for members and guests to bring the family out for basketball. Half court games are only during this time. There are no full court games during Family Shootaround hours. All participants must sign in at the front desk and wear a wristband during the play.

No one can believe that the over 6, 300-kilometre Great Wall might disappear some day. Believe it or not, the Great Wall is being destroyed by people. Less than 20 percent of the Great Wall built in the Ming Dynasty is still perfect, and about 80 percent is in danger. 

The Great Wall can be called "great" mostly because of its amazing length. If we do nothing to save the Great Wall, it will become wasteland rather than a historic site. The Great Wall is actually a series of walls built and rebuilt by different dynasties over the past 2, 000 years. It began in the Qin Dynasty, and lasted into the Ming Dynasty. The parts built before the Ming Dynasty have nearly disappeared. People are familiar with sections such as Badaling in Beijing and Jiayuguan Pass in Gansu, because they have been open to tourists for many years. But those sections far away from the public eyes have been almost forgotten. 

Few local people knew the 3-metre-high walls made of earth and stones beside them are part of the Great Wall. The lack of knowledge is considered as one of the main reasons behind humans. 

The bricks on the Great Wall are carried off by countryside people to build their houses. Rubbish is spread over the battlements. Those who destroyed and are destroying the Great Wall know its name, but don't know its cultural meaning. The local farmers not only carried off the body of the Great Wall but dug out the entire base. 

It is necessary to protect the Great Wall. First of all, the officials should be aware of the importance of the Great Wall. Young Chinese should know more about the nation's great civilisation and learn to love it.