综合填空（共10空，计10分）阅读短文，根据短文内容及首字母提示，在空白处填人一个适当的单词。
The Great Wall of China has a history of o_____ 2000 years. It runs from the east
t   the west in North China. It is the  l     wall in the world. It is often called “Ten-Thousand-Li Great Wall”. It is one of the “Seven Wonders of the  A_____ World ”.
The Great Wall is w    enough for ten men to walk side by side. Horses can also run along it, too. The Great Wall was made of stones and bricks (砖).There are many h____ stones on each side and on the highest part. But now some parts of it are worn out.
There are tall watchtowers along the Great Wall. O_____ upon a time, the soldiers kept watching the enemies (敌人) in the watchtowers day and night. They made fire on the towers to tell each other w____ the enemies came.
Nowadays we don’t use the Great Wall to keep away the enemies a_______. It is a famous place of interest to all the people in the world. Every year t_______ of people come to visit it from all over the world.