根据汉语意思完成句子。（每空一词）
1.谁拆毁了这些古城墙？
Who _______ _______ the old city walls?
2.人们把黄河当作我们中 * * 的象征。
People _______ the Yellow River _______ a symbol of the Chinese nation.
3.科学家们发现这个帝王墓破旧不堪了。
Scientists found that the emperor’s tomb was _______ _______.
4.从明天起，人们开始重建家园。
From tomorrow _______, the workers are beginning to _______ their homes.
5.这座桥有六百多年的历史了。
The bridge is _______ _______ 600 years old.