随着这条河流流经峡谷，河面平均每公里下降了18米。

As the river flows through the canyon, it drops an average of 18 meters per kilometer.

youdao

随着这条河流流经峡谷，河面平均每公里下降了18米。

As the river flows through the canyon, it drops an average of 18 meters per kilometer.

youdao