Most of the people who appear most often and most gloriously in the history books are great conquerors and generals and soldiers, whereas the people who really helped civilization forward are often never mentioned at all. We do not know who first set a broken leg, or launched a seaworthy boat, or calculated the length of the year, or manured(施肥)a field; but we know all about the killers and destroyers. People think a great deal of them, so much so that on all the highest pillars (纪念柱) in the great cities of the world you will find the figure of a conqueror or a general or a soldier. And I think most people believe that the greatest countries are those that have beaten in battle the greatest number of other countries and ruled over them as conquerors. It is just possible they are, but they are not the most civilized.

    Animals fight; so do savages (野蛮人); hence to be good at fighting is to be good in the way in which an animal or a savage is good, but it is not to be civilized. Even being good at getting other people to fight for you and telling them how to do it most efficiently －this, after all, is what conquerors and generals have done －is not being civilized. People fight to settle quarrels. Fighting means killing, and civilized peoples ought to be able to find some way of settling their disputes other than by seeing which side can kill off the greater number of the other side, and then saying that that side which has killed most has won. And it not only has won, but, because it has won, has been in the right. For that is what going to war means; it means saying that might is right.

    That is what the story of mankind has on the whole been like. Even our own age has fought the two greatest wars in history, in which millions of people were killed or disabled. And while today it is true that people do not fight and kill each other in the streets －while, that is to say, we have got to the stage of keeping the rules and behaving properly to each other in daily life － nations and countries have not learnt to do this yet, and still behave like savages.

    Polar bears are one of the most popular animals for people. Polar bears are different from every other bear in the world. This is because polar bears have white fur. However, there are many facts about polar bears that people might not be aware of .

    The skin of polar bears is black, which according to thinkquest.org allows them to absorb more heat from the sun. Polar bear fur is transparent , because it is made up of hollow guard hairs. Loc.gov explains that the reason polar bears display white fur is that when the sun hits the fur ,the hollow spaces in the hair scatter the light. Since none of the light is absorbed, the light reflected back appears white to human eyes.

    Polar bears' conservation status is considered close to extinction. Global warming is considered the main cause of the decline in polar population. Polar bears use ice floats to hunt for their food. However, these ice floats are melting so polar bears are starting to drown in the search for food, and the food is becoming more difficult to get. Contrary to popular belief, polar bears do not eat penguins, because polar bears are not found in the Antarctic region of the world. Polar bears are only found around the Arctic Circle. Polar bears do not drink water. They get all the water they need from the prey they eat.

    FES. Gov specifies that polar bears are considered the largest land carnivores(食肉动物) in the world. The polar bear weight ranges between 700--1,500 pounds. Since the polar bear habitat is melting away, their main evolutionary advantages are fading. Polar bears are not able to use their camouflage(伪装) to find prey in habitats not covered with snow. Polar bears do not hibernate(冬眠). However, when the weather gets uncomfortable, or mothers give birth, polar bears will dig themselves a hidden home.

    What can we do to help save the polar bears? We can donate to organizations like the World Wildlife Fund, reduce our carbon footprint, and send letters to politicians explaining to them that we need to set up more preserves to help save the polar bear habitat.

    Our brains work in complex and strange ways.There are some people who can calculate the day of the week for any given date in 40,000 years,but who cannot add two plus two.Others can perform complex classical piano pieces after hearing them once,but they cannot read or write.

    Dr.J.Langdon Down first described this condition in 1887.He called these people idiot savants.An idiot savant is a person who has significant mental impairment（损伤）,such as in autism（孤独症，自闭症）or retardation.At the same time,the person also exhibits some extraordinary skills,which are unusual for most people.The skills of the savant may vary from being exceptionally gifted in music or in mathematics,or having a photographic memory.

    One of the first descriptions of a human who could calculate quickly was written in 1789 by Dr.Benjamin Rush, an American doctor.His patient,Thomas Fuller,was brought to Virginia as a slave in 1724.It took Thomas only 90 seconds to work out that a man who has lived 70 years,17 days,and 12 hours has lived 2,210,500,800 seconds. Despite this ability,he died in 1790 without ever learning to read or write.

    Another idiot savant slave became famous as a pianist in the 1860s.Blind Tom had a vocabulary of only 100 words,but he played 5,000 musical pieces beautifully.

    In the excellent movie Rain Man,made in 1988 and available on video cassette,Dustin Hoffman plays an idiot savant who amazes his brother played by Tom Cruise,with his ability to perform complex calculations very rapidly.

    Today we more clearly recognize that the idiot savant is special because of brain impairment.Yet not all brain impairment leads to savant skills.Some studies have shown that people who have purposeful interruption of the left side of the brain can develop idiot savant skills.However few people wish to participate in such experiments.There are many excellent reasons for not undergoing unnecessary experimentation on one's brain.The term idiot savant is outdated and inappropriate.Virtually all savants have a high degree of intelligence and are thus not idiots.

    The Great Pyramid(金字塔)was built nearly 5,000 years ago for a king called Khufu. It is on the west bank of the Nile River. In fact, all the pyramids along the Nile River are on its west bank. The ancient Egyptians thought of the rising of the sun as the beginning of life and the setting of the sun as the end of life. This is why their bodies were buried on the west of the Nile.

    It is very hard to realize just how big the Great pyramid is. It has over 2,000,000 pieces of stones. Most of these big stones weigh two and a half tons each. Some even weigh fifteen tons. Without machinery, the ancient Egyptians cut and moved and lifted each of these stones. Almost all the stones came from the east bank of the Nile, and they were taken across the river in boat. It took more than 100,000 people twenty years to build the Great Pyramid.

    The Great Pyramid is over 450 feet high today. Each of the sides of the Pyramid is 755 feet long. It takes about twenty minutes to walk all the way around it.

    On the way to my company, I was driving behind a small truck. I was a few minutes late and watching the two men ahead of me talking in that slow truck made me angry.

    The light turned green, but the truck was still moving very slowly. I became impatient, so I turned right to go past it. Suddenly, a new blue Chevy Silverado was rushing by. I tried to stop, but my car hit the side of the Chevy.

    "Pow!" I heard a big noise and then I realized that an accident happened. For a moment, just a moment... I asked if I was OK, and honestly, I was waiting for people to come over and help me. Those thoughts didn't last long, as the answer came into my mind that the air bag had saved me. Luckily, I was still alive.

    Slowly I opened the door. The warm, bright morning sunlight hit my face and I felt better. I saw the Chevy Silverado and I ran over to check if the driver in it was injured. "Are you OK？"I shouted loudly through the window. His head was down, eyes closed, and he didn't answer me.

    At that moment, I thought I was looking at a dead man. Full of fear, I shouted again, and knocked at the window heavily once more. His eyes started to open, and he slowly shook his head, "Yes."

    Once again, I said to myself, "How lucky I am!"

    It's a safe bet that a robot made your car and made your computer. Pretty soon, they could be making your bed and breakfast too.

     Increasingly, engineers are saying that robots are going to move out of research departments and into your home. Companies including General Electric are working on designs for small robots. Products like the Roomba, a robot that can clean floors, are flying off the shelves.

     What's behind this new robot revolution? It's partly a matter of technology. Devices that can recognize and respond to a human voice have been developed. There are now a few different ways for robots to move around. They can walk, crawl or ride on wheels. Robots are being made smaller and smaller. They are also becoming more and more able.

     A bigger part of the story is on the demand side. From the day the television remote control was invented, people around the world have searched for new ways to be lazy. Take into consideration that more and more people can afford robots, and the time seems ripe to introduce robots to the ordinary family.

     To be sure, robots that walk on two legs and talk like people are still a long way off. However, robots that do basic housework such as cleaning or gardening are sure to come out soon. One thing is certain—when these robots do come into our homes, it will change things forever.