After ruling the tennis world for almost five years,Roger Federer is adjusting to life at NO.2.But,like any king whose throne has been taken away,the Swiss star is already planning secretly bis return to power,beginning at this week's US Open.

    The problem is, many experts think he will never do it.They blame everything from age and tough competition to his racket and psychology.

    For years Federer, had enjoyed the view from the top.Competitors saw him as undefeated,and for the most part he was.However,before the 2008 season began,Federer had an illness that stole his strength and clearly affected his play on the court.Ever since,he has struggled to return to form,winning just two of his last 14 tournaments.

    "Twenty-seven is an age when your body starts talking back to you."tennis great John McEnroe told the New York Times.

    Pancho Sefura, another tennis great, noted that Federer is also facing a maturing crop of young talents."There are too many great players now,"he said,naming Britain's Andy  Murray,21,and Latvia's Ernests Gulbis,20.

    US magazine Sports Illustrated tennis columnist Jon Wertheim suggested that part of Federer's problem could be his insistence on using a small racket.He says that the smaller head demands ball control.But we see time and again that racket makers try to get players to use a certain stick-one they would like to market to consumers and it has a negative effect on the professional game.

    Sports psychologist Jim Loehr told the Times that Federer is probably feeling "a sense of doubt"after being considered as undefeated for so long.If Federer is to recover his state of being undefeated,Loehr said he must overcome his doubt."Federer doesn't need fame and money.But he has to get better.He has to go t.o a whole new level.That's the only way he stays in the game," he said.

    As for beginning his first Grand Slam in ages as the NO.2 seed, Federer said it might be for the best."Five years almost,I was expected to win every tournament I entered,"he said,"so maybe Rafael Nadal now feels what I had to feel for a very long time.It will be interesting to see how he handles it."

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    Many people go to school for an education. They learn languages, history, geography, physics, chemistry and mathematics. Others go to school to learn a skill so that they can make a living. School education is very important and useful. Yet no one can learn everything from school. A teacher, no matter how much he knows, cannot teach his students everything they want to know. The teacher's job is to show his students how to learn. He teaches them how to read and how to think. So, much more is to be learned outside school by the students themselves.

    It is always more important to know how to study by oneself than to memorize some facts or a formula （公式）. It is usually quite easy to learn a certain fact in history or a formula in mathematics. But it is very difficult to use a formula in working out a maths problem. Great scientists, such as Einstein, Newton and Galileo didn't get everything from school. But they were all so successful. They invented so many things for mankind.

Above all, they knew how to use their brains.

    Golden Gate Bridge

    Located in San Francisco, the Golden Gate Bridge started in the year 1933 to connect the San Francisco Peninsula with Marin County. It was finally thrown open to public traffic in 1937. It cost $25.7 million in the construction. Till the year 1957, the Golden Gate Bridge, at a length of 2,737 meters, was the longest suspension bridge in the world.

    Brooklyn Bridge

    The Brooklyn Bridge is located in Brooklyn. It is one of the oldest suspension bridges in the United States, having been opened in the year 1883. The length of the bridge is 1,843 meters. The bridge has been featured in several Hollywood movies.

    George Washington Bridge

    Also known as the Hudson River Bridge and the Columbus Bridge, the George Washington Bridge which connects Fort Lee to Manhattan came into use in 1931 after a construction period of almost 4 years. It is a two level suspension bridge that cost about $52 million to build.

    Mackinac Bridge

    This is the third biggest suspension bridge in the world at a length of 8,038 meters. The architect of this bridge was Dr. David B. Steinman, who directed the construction of the bridge which started in the year 1954 and opened to the public in 1958. People using this bridge are charged a certain amount of money.

Navajo Bridge

    Located in Arizona, this bridge crosses the Colorado River and is almost 250 meters long. The construction of this bridge started in the year 1927, ending two years later, costing $390,000. In the 1990s, a second bridge was built which was opened to the public in 1994. The first bridge is now used only by pedestrians.

    Elephants have impressed us for centuries. They are big, clever, and sociable. But what if someone told you that they may also hold the key to fighting cancer (癌症)?

    People have been wondering why elephants do not develop cancer, even though they have lifespans (寿命) that are similar to humans, living for around 50 to 70 years.

    Now scientists believe they know why. A team at the University of Chicago, US has found that elephants carry a large number of genes that stop tumors (肿瘤) from developing. To be precise, they found 20 copies of an anti­tumor gene called TP53 in elephants. Most other species, including humans, only carry one copy.

    According to the research, which was recently published on the online science network BioRxiv, the extra copies of the gene improved the animal's sensitivity to DNA damage. This lets the cells quickly kill themselves when damaged before they can go on to form deadly tumors.

    “An increased risk of developing cancer has stood in the way of the evolution of large body sizes in many animals，” study author Dr. Vincent Lynch told The Guardian. If every living cell (细胞) has the same chance of becoming cancerous, large creatures with long lifespans like whales and elephants should have a greater risk of developing cancer than humans and mice do. But across species, the risk of cancer does not show a connection with body mass.

    This_phenomenon was found by Oxford University scientist Richard Peto in the 1970s and later named "Peto's paradox". Evolutionary (进化的) biologists believe it results from larger animals using protection that many smaller animals do not. In the elephant's case, the making of TP53 is nature's way of keeping this species alive.

    The study also found that when the same genes were brought to life in mice, they had the same cancer resistance (抵抗) as elephants. This means researchers could use the discovery to develop new treatments that can help stop cancers from spreading or even developing in the first place.

    "Nature has already figured out how to prevent cancer, " said Joshua Schiffman, an oncologist at the School of Medicine, University of Utah, US.

    “It's up to us to learn how different animals tackle (处理) the problem so we can use those strategies to prevent cancer in people.”

Atlantis Waterpark is a great day of fun featuring pools, a giant dumping bucket, hair-raising waterslides, great food, cool souvenirs and fun-filled activities for kids and adults of all ages! Atlantis is open annually from Memorial Day weekend through Labor Day. Our snack bar – Neptune Reef – features all the food, beverages and sweets you'd hope to find.

Bear Path Acres Zoo is a non-profit animal shelter. You get to meet the animals up close and personal! We take pride in working with each animal to make it a wonderful learning experience. We are conveniently located in Southampton County, just 9 miles south of Franklin. Spend an hour or pack your lunch and spend the day!

Belvedere Plantation is a 645 acre heritage farm, built in the 1760s on the historic Rappahannock River near Fredericksburg, Virginia. It is a working farm, with grain crops such as corn, wheat and soybeans. Come for picnics and parties. Enjoy fall harvest time with pumpkin picking, bonfires, and even a cornfield maze. Group and educational programs available.

Come on out to Hunt Club's Petting Farm for a day of family fun on the farm. Visit everyone's favorite place where you can spend all day feeding and petting our goats, sheep, chickens, and more! Take the time to explore the farm so you don't miss the pigs, rabbits and cows. Our guests love to get to know the animals and we encourage it!

Do you like doing exercise? Do you want to know the benefits from the exercise? Let's learn something about exercise. 

Exercise is any action that gets you moving. You can run, ride a bike, swim, jump rope or row a boat. It's all good for you! 

There are three kinds of exercise. One is stretching(拉伸). You may do this in dance, yoga or at the gym. When you stretch, you keep your muscles(肌肉)bendable(可弯曲的). 

Aerobic exercise(有氧运动)makes your heart beat fast. You get this kind of exercise when you walk or run. Your heart beats fast when you swim, too. 

The last kind of exercise makes your muscles strong. You build strong muscles when you lift weights. When you sprint or run fast, you make your muscles strong, too. 

You get exercise when you play tag and hide and seek. Leapfrog and ball games are also good to do. So go outside and have fun! If you keep on doing exercise, you will know the more exercise you do, the healthier and happier you will be.