尽量词汇比较简单，不需要太长 100-200个单词就可以了
參考答案:The Great Wall of China (literally "long city wall") is a series of stone and earthen fortifications in China, built between 5th century BC and the 17th century to protect the northern borders of the Chinese Empire during the rule of successive dynasties. Several walls, referred to as the Great Wall of China, were built since the 5th century BC, the most famous being the one built between 220 BC and 200 BC by the first Emperor of China, Qin Shi Huang; this wall was located much further north than the current wall built during the Ming Dynasty, and little of it remains.
The Great Wall is one of the existing megastructure and the world's longest man-made structure, stretching over 6,352 km (3,948 miles) from Shanhai Pass in the east to Lop Nur in the west, along an arc that roughly delineates the southern edge of Inner Mongolia.