横向
1
Largest river in South America
4
Line dividing two countries
5
Deep narrow valley with steep sides
6
Dry land with little rainfall
9
Ocean between Americas and Europe/Africa
10
Wearing away of land by water or wind
纵向
2
Half of the Earth
3
Mountain that can erupt with lava
7
Land surrounded by water on three sides
8
Vast body of salt water