Some people seem to have unusual memories. Zheng Aiqiang, a "memory athlete" on TV show Super Brain, can remember 2,660 numbers in just one hour!

    You would think people like him must have special brains. But according to a recent study by researchers from America and Holland, the brain structure (结构) of ordinary people and 23 of the world's leading memory athletes shows no difference.

    Good memories can be trained. New research in the magazine Neuron suggests that a person will get a super memory with just six weeks of hard training.

    Researchers found that a technique (技巧) called loci, invented by the ancient Greeks, can greatly help improve memory.

    By using loci, you are using your imagination to improve the brain's memory networks. You can link (关联) something you need to remember with a place that you know very well. For example, to remember a list of numbers, imagine yourself walking through your house. Each thing is linked to a number. For example, zero could be the handle on the door and five could be the painting on the wall.

    In one study, some ordinary people were given 20 minutes to remember 72 nouns. At the beginning, they could only remember 26 words, but when they were taught loci, they could remember 62 words.

    "Not everyone can become a memory winner. But everyone using the technique can improve his memory greatly," said Boris Konrad, one of the researchers in the study.

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    Liu Tuchi, an 87­year­old man, has given away thousands of books to kids in five villages in Southwest China and built some reading rooms in the past 13 years by collecting and selling rubbish.

    "After selling the rubbish, I go to bookstores to search for good books," Liu said. When he has enough books, he sends them to the kids in the villages.

    Liu was an officer in Sichuan Province before retiring (退休) in 1993. "I passed by a primary school in Qilong Village in 2005 and was shocked by the poor conditions," he said. With old classrooms and broken desks, the students hardly had any books. So Liu took out more than 5, 000 yuan and raised more than 8, 000 yuan from his family and friends to give away books to the school. Since then, he has kept on giving away books to rural (农村的) kids.

    Liu's work has opened his new lifestyle (生活方式). He collects and sells waste, such as bottles and old newspapers. In 2008, Liu started building reading rooms. So far he has built more than 15 reading rooms. Liu always says, "Children in rural areas should not be left behind, especially in education."

    The world itself is becoming much smaller by using modern traffic and modern communication means. Life today is much easier than it was hundreds of years ago, but it has brought new problems. One of the biggest problems is pollution. To pollute means to make things dirty.{#blank#}1{#/blank#}We see it, smell it, drink it and even hear it. Man has been polluting the earth. {#blank#}2{#/blank#}Many years ago, the problem was not so serious because there were not so many people. When the land was used up or the river was dirty in one place, man moved to an-other place. But this is no longer true. Man is now slowly polluting the whole world. Air pollution is still the most serious. {#blank#}3{#/blank#}Water pollution kills our fish and pollutes our drinking water. Noise pollution makes us angry more easily.

    {#blank#}4{#/blank#}They stop people from burning coal in houses and factories in the city, and from putting dirty smoke into the air. Pollution by SO, is now the most dangerous kind of air pollution. It is caused by heavy traffic. We are sure that if there are fewer people driving, there will be less air pollution. The earth is our home. We must take care of it. {#blank#}5{#/blank#}And we must take care of the rise in pollution at the same time.

    Critical thinking(批判性思维) is trying to improve the way you think. People use critical thinking in every area of life to solve problems and evaluate claims(评估主张).

    Like every other skill, critical thinking takes practice. When a problem comes our way, we need to think critically to decide how to solve it. When we see an advertisement, for example, we should stop and think. Advertisements are made to make people feel certain that they are true, and then people can buy the products. But is what the advertisement says true? Is it making a claim? Or does it only interest us? Critical thinking is important and stops us from making poor choices. In fact, we are using it if we ask questions naturally about what we see.

    Practice makes perfect. While you are growing in critical thinking, you'll become a wiser and more thoughtful person. There are many ways of doing practice. Here are a few.

    Read about a topic people disagree on. Look at articles or books on all sides of the subject. For each side of the subject, think carefully and evaluate it.

    When you see or hear a claim, ask questions about it. Who is making the claim and why?

    Evaluate your own thinking. Where and why do you think uncritically? How can you improve?

    Critical thinking should be part of everything we do. It may help you to succeed at work or school. Make yourself into a habit of critical thinking. Change your thoughts and change your world.

    Have you ever ridden a Ferris wheel lately? Can you imagine the flying feeling as you are pulled up to the top and then moved down to the bottom quickly again?

    Today a Ferris wheel is usually 40 to 60 feet tall. That seems very high when you are on the top looking down. But the first Ferris wheel was 264 feet high- taller than a twenty-story building! Can you imagine the view from the top of that?

    The first Ferris wheel was built for the 1893 World's Fair in Chicago. The people who planned the fair were looking for an attraction that would bring people to Chicago. George Ferris handed a drawing of a giant wheel that people could ride on. At first everyone laughed at his strange idea. But Mr Ferris did not give up, and finally the idea was accepted. The ride opened in June of 1893.

    Today's Ferris wheels have 12 to 16 seats, which each carry 2 or 3 people. But that first one had 36 enclosed cars, each holding 60 passengers. When filled, it carried 2,160 people. During that summer in Chicago, about 1.5 million people rode the Ferris wheel.

After the fair, the ride was moved to a nearby amusement park built especially to show off the wheel. In 1904, it was moved again一to St. Louis for the Louisiana Purchase Exposition. After the fair there, the wheel stood unused. In 1906, it was finally sold to a company for scrap metal(废金属).

    Luckily a Chicago bridge builder, W.E. Sullivan, figured out how to make a smaller Ferris wheel that could easily be taken apart and put together. In 1906, he started the company that still makes many of the Ferris wheels used today.

    But, whenever you ride one, remember that it all began with George Ferris's strange idea!