题目内容
动脑筋想一想,下面的空应该怎么填?
It is believed that the Great Wall was built for ________(protect)the northern border of China.
答案:protecting
练习册系列答案
相关题目
题目内容
动脑筋想一想,下面的空应该怎么填?
It is believed that the Great Wall was built for ________(protect)the northern border of China.