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The Great Wall of China

　　The Great Wall of China, the longest wall in the world, runs across north China like a huge dragon．It winds its way from west to east, across deserts, over mountains, through valleys, till at last it reaches the sea．It is one of the wonders of the world．And it was one of the few man-made objects on earth that could be seen by the astronauts who landed on the moon．

　　The Great Wall has a history of over twenty centuries．The first part of it was built during the Spring and Autumn Period(770 B．C．-476 B．C．)．During the Warring States Period(475 B．C．-221 B．C．), more walls were put up to defend the borders of the different kingdoms．

　　In 221 B．C．, the Kingdom of Qin united the different parts of China into one empire．To keep the enemy out of his empire．Emperor Qin Shihuang had all the walls joined up．Thus the Great Wall came into being．Since then, it has often been added to, rebuilt and repaired, especially during the Ming Dynasty(1368-1644)．

　　The Great Wall, which is called in Chinese“The Ten-Thousand-li Great Wall”, is actually more than 6000 kilometers long, 6-7 meters high and 4-5 meters wide．In most places it is wide enough for five horses or ten men to walk side by side along the top．It has great gateways which connect the main roads of north China．

　　Every few hundred meters along the wall there are watch towers, ?where soldiers used to keep watch．When the enemy came, fires were lit and at the same time guns were fired to warn soldiers at other towers．One column of smoke with one gunshot meant an enemy troop of about 100, two columns with two shots meant 500．In this way, a warning message could be sent 500 kilometers within a few hours．

　　It was very difficult to build and rebuilt such a great wall over wild and distant country without any modern machines．All the work had to be done by hand．Many people were forced to work on the wall far away from their homes．They lifted earth in baskets, passed bricks from hand to hand and dragged heavy stones with ropes over their shoulders．Their living conditions were terrible．Thousands of men died and were buried under the wall they built．The Great Wall was made not only of stone and earth, but of the flesh and blood of millions of men．

　　After the Great Wall was rebuilt hundreds of years ago, no more work was done on it until the People’s Republic of China was founded．After that, parts of the Wall were repaired．On both sides of it new cities appeared, trees were planted, and deserts became grasslands．The old Great Wall took on a new look．

　　Today the Great Wall has become a place of interest not only to the Chinese people, but also to the people from all over the world．Many of them have come to know the famous Chinese saying,“He who does not reach the Great Wall is not a true man．”

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