In addition to n______ rivers,the ancient Chinese people also dug many canals.
问题描述：
In addition to n______ rivers,the ancient Chinese people also dug many canals.
答
natural
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祝你学习进步,更上一层楼!(*^__^*)】谢谢啦，还有一个疑问Our school has been holding a number of e______ to raise money for poor student.evenings（晚会）