英语听力：自然百科 探索世界奥秘之万里长城 Unit3（在线收听）

Throughout their long history, the Chinese have been farmers. If you are committed to your land, you stay put and accumulate possessions--land, livestock and homes that you fill with furniture and goods. It's a way of life constantly threatened by nomadic raids. And so from earliest times, the Chinese built walls, walls around their homes, walls around their cities and walls around their country to keep the have-nots out.

Wall building was so deeply ingrained in the Chinese mentality that the Chinese character for city is also the Chinese character for wall. Building a wall surrounding a country the size of China needed a man of prodigious ego and power. A man so powerful that China is named after him-- Emperor Qin, the first emperor of China. He began two centuries before the birth of Christ with a wall stretching more than 4, 000 miles from Lintao in modern central China, across deserts, over mountains and plateau, all the way to the Korean border. Incredibly, it was built in only 12 years. Imagine building a wall, 32 feet high, 15 feet wide from New York to California without any modern equipment. The Emperor Qin was a remarkable man. Originally, Qin ruled only a small state in the northwest corner of China, but that wasn't enough for him. Qin built an invincible army. And one by one, he conquered his neighbors. It was said Qin ate up his neighbors as a silkworm devours a leaf. With all of China under his rule, Emperor Qin standardized measurements, created a single currency, the world's first euro. That's the good news. The bad news is that he was a paranoid tyrant who rewrote history to begin with himself.

Qin's tomb reveals both how magnificent and terrifying his reign must have been. Here in 1974, just to the east of his tomb, a vast buried army was discovered, a terracotta army guarding its emperor from evil spirits.