Memory, they say, is a matter of practice and exercise. If you have the wish and really made a conscious（自觉的）effort, then you can quite easily improve your ability to remember things. But even if you are successful, there are times when your memory seems to play tricks on you.

    Sometimes you remember things that really did not happen. One morning last week, for example, I got up and found that I had left the front door unlocked all night, yet I clearly remember locking it carefully the night before.

    Memory “trick” work the other way as well. Once in a while you remember not doing something, and then find out that you did. One day last month, for example, I was sitting in a barber（理发师）shop waiting for my turn to get a haircut, and suddenly I realized that I had got a haircut two days before at the barber shop across the street from my office.

    We always seem to find something funny and amusing（有趣的）in incidents caused by people's forgetfulness or absent-mindedness. Stories about absent-minded professors have been told for years, and we never got tired of hearing new ones. Unfortunately, however, absent-mindedness is not always funny. There are times when “trick” of our memory can cause us great trouble.

A Competitive Sport

    Cheerleading

    Over the years, cheerleading has taken two primary forms: game-time cheerleading and competitive cheerleading. Game-time cheerleaders' main goal is to entertain the crowd and lead them with team cheers, which should not be considered a sport. However, competitive cheerleading is more than a form of entertainment. It is really a competitive sport.

    Competitive cheerleading includes lots of physical activity. The majority of the teams require a certain level of tumbling (翻腾运动) ability. It's a very common thing for gymnasts, so it's easy for them to go into competitive cheerleading. Usually these cheerleaders integrate lots of their gymnastics experience including their jumps, tumbling, and overall energy. They also perform lifts and throws. This is where the “fliers” are thrown in the air, held by “bases” in different positions that require strength and working with other teammates.

    Competitive cheerleading is also an activity that is governed by rules under which a winner can be declared. It is awarded points for technique, creativity and sharpness. Usually the more difficult the action is, the better the score is. That's why cheerleaders are trying to experience great difficulty in their performance.

    Besides, there is also a strict rule of time. The whole performance has to be completed in less than three minutes and fifteen seconds, during which the cheerleaders are required to stay within a certain area. Any performance beyond the limit of time is invalid.

    Another reason for the fact that competitive cheerleading is one of the hardest sports is that it has more reported injuries. According to some research, competitive cheerleading is the number one cause of serious sports injuries to women. Emergency room visits for it are five times the number than for any other sport, partially because cheerleaders don't use protective equipment. Smiling cheerleaders are thrown into the air and move down into the arms of the teammates, which may easily cause injuries. Generally, these injuries affect all areas of the body, including wrists, shoulders, ankles, head, and neck.

    There can be no doubt that competitive cheerleading is a sport with professional skills. Hopefully, it will appear in the Olympics since cheerleaders are just as athletic and physically fit as those involved in the more accepted sports. It should be noted that it is a team sport and even the smallest mistake made by one teammate can bring the score of the entire team down. So without working together to achieve the goal, first place is out of reach.

    Chinese consumers' crazy appetite for luxury goods and services appears unstoppable,with just 2 percent of the Chinese population responsible for one-third of the world's luxury items.

    As China's economic miracle develops,the market opportunities for all sorts of luxury goods and services are increasing.Luxury consumption in China now extends ways beyond well-known car,clothing and jewelry brands.For example,the luxury jet market in China is the fastest-growing in the world,even outstripping that of the United States, with a market share of 25 percent.This trend appears to continue,with 20 to 30 percent growth expected in China, compared with only 2 to 3 percent in the US.But more importantly,China's luxury jet market growth represents a major development in the private consumption of luxury items.

    China's high-quality red wine market also provides evidence of the growth in private consumption of luxury goods.In 2013,China became the largest market for red wine in the world,even overtaking France,with l.86 billion bottles consumed in China last year.Over the past five years,China's red wine consumption has grown 136 percent.

    According to my ongoing consumer research in this area while working at the University of International Business and Economics in Beijing,public consumption of such expensive global luxury brands such as Prada and Armani is easily explained by the desire to "gain face" and publicly display social climbing through material possessions.On the other hand,it is "self-reward" that lies behind consumer motivation in this area.Chinese consumers who have experienced rapid financial and economic gains appear particularly prone to the need to reward themselves for their success.But this has little to do with "gaining face" and impressing others and much more to do with the need for personal contentment.

    Finally,the growth in private luxury consumption in China is set to continue in part due to the maturity of the Chinese consumer and advancement of Chinese consumer culture generally.

    Very few people enjoy going to the dentist, especially for a filling. Often fillings need to be replaced during the patients' lifetime. But is filling the cavity (蛀洞)with a foreign material really the best treatment? What if the tooth could repair itself with its own material–dentine(齿质)? Researchers at King's College London have found a process that may replace the traditional method.

    Paul Sharpe of King's College says a new treatment for cavities is simpler. It uses a drug that causes the tooth to fill in the hole naturally with dentine. "It involves putting a drug in the hole. It excites a natural process, which starts to occur anyway following the damage, so you can actually get the big hole repaired and the repair is a production of the natural material, the dentine."

    Usually a new drug requires repeated testing before it is approved for treatment. However, this drug that produces the re-growth in teeth has already been approved. It is a drug used to treat Alzheimer's disease and other disorders of the nervous system. Researchers explain that they use only a small amount and they use it locally. Usually that means the medicine is put directly on the affected area. It does not travel through the patient's blood.

    Nigel Carter heads Britain's Oral Health Foundation. He describes the new treatment as an exciting possibility for dental care. But Carter also has a warning. "Actually re-growing the tooth that has been lost with a cavity would be really a huge step forward. But, it's also important that we remember that we shouldn't be getting the cavity in the first place. We're talking about a totally preventable disease."

    As a result of pollution, Lake Erie, on the borders of the USA and Canada, is now without any living things.

    Pollution in water is not simply a matter of “poisons” killing large numbers of fish overnight, Very often the effects of pollution are not noticed for many months or years because the first organisms（生物体）to be affected are either plants or plankton. But these organisms are the food of fish and birds and other creatures. When this food disappears, the fish and birds die too. In this way a whole food chain can be wiped out, and it's not until dead fish and water birds are seen at the river's edge or on the seashore that people realize what is happening.

    Where do the substances which pollute the water come from? There are two main sources of sewage（污水）and industrial waste . As more detergent（洗涤剂）is used in the home, so more of it is finally put into our rivers, lakes and seas . Detergents harm water birds, dissolving the natural substances which keep their feathers water - proof. Sewage itself, if not properly treated, makes the water dirty and prevents all forms of life in rivers and the sea from receiving the oxygen they need. Industrial waste is even more harmful as there are many highly poisonous things in it, such as copper and lead（铅）.

    So, if we want to stop this pollution, the answer is simple: sewage and industrial waste must be made clear before flowing into the water. It may already be too late to save some rivers and lakes, but others can still be saved if the correct action is taken at once.

    Qing-Feng Steamed Dumpling Shop. Daniang Dumpling. McDonald's. What do these companies have in common?

    Well, besides all being fast food chains, their logos are all red. And it's not a coincidence. Color is one of the many that companies use to connect with customers. And if fast food wasn't hard enough, those red logos might make it even harder to ignore.

    The average human can see ten million colors, but red is special. It's one of the first colors our ancient ancestors thought important enough to name. Early human languages were uncolorful. There were words for “black” and “white” and “red” but not much else.

    As a result, we have a deeper connection to red than any other color and we react to it in certain ways that actually play to fast food companies' advantage. For starters, researchers have found that red can cause a sense of urgency. On top of that, it also has an ability to whet (刺激) our appetites. And when you pair those two together, you've got the perfect recipe to attract hungry customers who want food, fast.

    So the red logo isn't just a welcoming sign. It's a seduction (诱惑) for your brain. Now, it's unclear why red makes us feel this way. But perhaps it has something to do with where the word comes from. Many ancient languages first named red from their word for “blood”. But red's bloody beginning has transformed. During medieval times, for example, red was worn by royals as a status symbol. And today, brides in many parts of India are married in red dress.

    In fact, red is one of the few colors today that cultures all over the world view positively. And it's no wonder companies attach so much importance to their logos. After all, we're a visual species. Despite having five senses, 80% of the information our brains process on a daily basis comes from our eyes. And according to marketing company WebPageFX, nearly 85% of consumers say the main reason they choose one product over the other is color.

    Just think what McDonald's would look like in blue, green, or pink! It's just not the same, right?