The discussion on renewable energy has been going on for at least a decade and people have relied on fossil fuels almost entirely for more than a century. However, the situation when fossil fuels were the most efficient and the cheapest source of energy has been left far in the past. Many countries such as Germany and Sweden have already made significant efforts to fix this situation, employing numerous power plants working on the renewable resources of energy. The most effective among these resources is geothermal（地热的）energy.

    Geothermal energy does not depend on the world's economic and political situation as strongly as fossil fuels do. Besides, extracting（提炼）fossil fuels adds to the price of energy produced from them. Therefore, geothermal energy is much cheaper than traditional ones, saving up to 80% of the costs over fossil fuels.

    Being a renewable resource, geothermal energy produces less waste and pollution than traditional energy sources. In geothermal systems, carbon dioxide makes up about 10% of air produced. Overall, in order to produce the electricity that can be used for one hour, the geothermal systems produce 0.1 pound of carbon dioxide and other harmful gases. For a comparison, a power plant producing from gas produces up to 2 pounds of carbon dioxide into the atmosphere, and those power plants that work on coal（煤）produce an astonishing 3.6 pounds of greenhouse gases.

    Low costs is another reason why using geothermal power plants should be the first choice for many countries. Geothermal heat systems require 25% to 50% less energy for work compared with the traditional systems for heating or cooling. Besides, geothermal equipment is less big: due to the very nature of geothermal energy, geothermal power plants have only a few moving parts, all of which can be easily sheltered inside a relatively small building. What's more, the life span of geothermal equipment is rather long. All these make geothermal power stations easy to build and keep.

B

Find Your Adventure at the Space and Aviation(航空) Center

    If you're looking for a unique adventure, the Space and Aviation Center (SAC) is the place to be. The Center offers programs designed to challenge and inspire with hands-on tasks and lots of fun.

    More than 750,000 have graduated from SAC, with many seeking employment in engineering, aviation, education, medicine and a wide variety of other professions. They come to camp, wanting to know what it is like to be an astronaut or a pilot, and they leave with real-world applications for what they're studying in the classroom.

    For the trainees, the programs also offer a great way to earn merit badges(荣誉徽章). At Space Camp, trainees can earn their Space Exploration badge as they build and fire model rockets, learn about space tasks and try simulated(模拟) flying to space with the crew from all over the world. The Aviation Challenge program gives trainees the chance to earn their Aviation badge. They learn the principles of flight and test their operating skills in the cockpit(驾驶舱) of a variety of flight simulators. Trainees also get a good start on their Wilderness Survival badge as they learn about water- and land-survival through designed tasks and their search and rescue of ＂downed＂ pilot.

    With all the programs, teamwork is key as trainees learn the importance of leadership and being part of a bigger task.

    All this fun is available for ages 9 to 18. Families can enjoy the experience together, too, with Family Camp programs for families with children as young as 7.

    Stay an hour or stay a week — there is something here for everyone!

    For more details, please visit us online at www.oursac.com.

    Unlike modern animal scientists, dinosaur scientists cannot sit on a hillside and use telescopes to watch dinosaurs in order to know how they lived and whether they were good parents. Instead, they have to search hard for information from dinosaurs' fossils(恐龙化石) because dinosaurs died out millions of years ago.

    It's very difficult for the scientists to reach an agreement because different results can be got from the same fossils. Many fossils of the same kind of dinosaurs have been dug out from one place. They might have formed when an entire group of dinosaurs got stuck(陷入)all at once. Or they might have been the result of dinosaurs getting stuck one after another over a course of a few centuries. Thus we can say that dinosaurs might have in the first case lived in big groups and in the second lived alone.

    Though there are two different results, dinosaur scientists now generally agree that at least some kinds of dinosaurs lived in big groups. “That's pretty much settled at this point.” Says Paul Sereno. A kind of dinosaurs called Sauropods left behind tracks in the western United States that appear to run north and south, suggesting that they even moved long distances together.

    As to whether dinosaurs cared for their young, dinosaur scientists have turned to the closest living relatives of dinosaurs, birds and crocodiles for possible models. Birds give a lot of care to their young, while crocodiles just help their young to the water. The discovered fossils of dinosaurs sitting on their eggs and staying with their young suggest the parents were taking care of their babies, but we still cannot say that all dinosaurs did the same.

    There is still a long way to go before the above questions could be answered. Dinosaur scientists will have to find more proof to reach an agreement.

    No one has a temper naturally so good, that it does not need attention and cultivation, and no one has a temper so bad, but that, by proper culture, it may become pleasant. One of the best disciplined tempers ever seen, was that of a gentleman who was naturally quick, irritable, rash, and violent; but, by taking care of the sick, and especially of mentally deranged (疯狂的) people, he so completely mastered himself that he was never known to be thrown off his guard.

    There is no misery so constant, so upsetting, and so intolerable to others, as that of having a character which is your master. There are comers at every tum in life, against which we may run, and at which we may break out in impatience, if we choose.

    Look at Roger Sherman, who rose from a humble(低下的) occupation to a seat in the first Congress of the United States, and whose judgment was received with great respect by that body of distinguished men. He made himself master of his temper and cultivated it as a great business in life. There are one or two instances which show this part of his character in a light that is beautiful.

    One day, after having received his highest honors, he was sitting and reading in his sitting room. A student, in a room close by, held a mirror in such a position as to pour the reflected rays of the sun directly in Mr. Sherman's face. He moved his chair, and the thing was repeated. A third time the chair was moved, but the mirror still reflected the sun in his eyes. He laid aside his book, went to the window, and many witnesses of the rude behavior expected to see the ungentlemanly student severely punished. He raised the window gently, and then-shut the window blind(百叶窗)!

    I can not help providing another instance of the power he had acquired over himself. He was naturally possessed of strong passions, but over these he at length obtained an extraordinary control. He became habitually calm and self-possessed. Mr. Sherman was one of those men who are not ashamed to maintain the forms of religion in their families. One morning he called them all together as usual to lead them in prayer to God. The "old family Bible "was brought out and laid on the table.

    Mr. Sherman took his seat and placed beside one of his children. The rest of the family were seated around the room, several of whom were now grown ups. Besides these, some of the tutors of the college were boarders in the family and were present at the time. His aged mother occupied a corner of the room, opposite the place where the distinguished Judge sat.

    At length, he opened the Bible and began to read. The child who was seated beside him made some little disturbance, upon which Mr. Sherman paused and told him to be still. Again he continued but again he had to pause to scold the little offender, whose playful character would hardly permit it to be still. At this time he gently tapped its ear. The blow, if blow it might be called, caught the attention of his aged mother, who now with some effort rose from the seat and tottered across the room. At length, she reached the chair of Mr. Sherman, and in a moment, most unexpectedly to him, she gave him a blow on the ear with all the force she could gather. “There, "said she, "you strike your child, and I will strike mine.”

    For a moment, the blood was seen mounting to the face of Mr Sherman. But it was only for a moment and all was calm and mild as usual. He paused; he raised his glasses; he cast his eye upon his mother; again it fell upon the book from which he had been reading. Not a word escaped him; but again he calmly pursued the service, and soon sought in prayer an ability to set an example before his household which should be worthy of their imitation. Such a victory was worth more than the proudest one ever achieved on the field of battle.

    See our editors' top 5 picks in print books and Kindle books, and discover our editors' picks for the best books of the year.

    # 1 Killers of the Flower Moon: The Osage Murders and the Birth of the FBI by David Grann

    In Killers of the Flower Moon, David Grami revisits a shocking series of crimes in which dozens of people were murdered in cold blood. Based on years of research and new evidence, the book is a masterpiece of narrative nonfiction.

    Kindle: $14.99 Hardcover: $ 17.37 Paperback: $15.36

    # 2 Little Fires Everywhere by Celeste Ng

    Little Fires Everywhere explores the weight of secrets, the nature of art and identity, and the fierce pull of motherhood and the danger of believing that following the rules can avoid disaster,

    Little Fires Everywhere is the perfect gift for the holidays!

    Kindle: $13.99 Hardcover: $ 20.96 Paperback: $ 12.95

    # 3 Bear Town by Fredrik Backman

    It is a novel about a forgotten town bothered by scandal and the amateur hockey team that might just change everything into a better place. Winning a junior ice hockey championship might mean everything to the residents of Beartown.

Kindle: $10.99 Hardcover: $ 12.95

    # 4 Exit West by Mohsin Hamid

    Profoundly intimate and powerfully inventive, Exit West tells an unforgettable story of love, loyalty, and courage that is both completely of our time and for all time.

Kindle: $12.99 Hardcover: $ 15.73 Paperback: $11

    # 5 Homo Deus: A Brief History of Tomorrow by Yuval Harari

    Yuval Noah Harari, author of the international phenomenon Sapiens, returns with an equally original and attractive book, turning his focus toward humanity's future, and our quest to upgrade humans into gods.

    Kindle: $17.99 Hardcover: $ 28.95 Paperback: $22.99

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Soccer is played by millions of people all over the world, but there have only been few players who were truly great. How did these players get that way—was it through training and practice, or are great players "born, not made"?

First, these players came from places that have had famous stars in the past—players that a young boy can look up to and try to imitate (模仿). In the history of soccer, only seven countries have ever won the World Cup. There has never been a great national team—or a really great player—from North America or from Asia.

Second, these players have all had years of practice in the game. Pele, who is often named as the greatest soccer of all time, was the son of a soccer player. He began to play soccer with his father when he was only three. Most players begin playing the game at the age of three or four.

Finally, many great players come from the same kind of neighbourhood—a poor, crowded area where a boy's dream is not to be a doctor, lawyer, or businessman, but to become a rich, famous athlete or entertainer (艺人). For example, Liverpool, which produced the Beatles, had one of the best English soccer teams in recent years. Pele practiced in the street with a "ball" made of rags (破布). And George Best learned the tricks that made him famous by bouncing the ball off a wall (对着墙壁踢球) in the slums (贫民窟) of Belfast.

All great players have a lot in common, but that doesn't explain why they are great. Hundreds of boys played in those Brazilian streets, but only one became Pele. The greatest players are born with some unique quality that sets them apart from all the others.