横向
1
Region between the two tropic lines
3
Area where water covers the soil
8
Large natural stream of water
9
Line dividing two countries
12
Deep narrow valley with steep sides
纵向
2
Goods sold to another country
4
Large area covered with trees
5
Largest ocean on Earth
6
Cold treeless Arctic plain
7
Land surrounded by water
10
Low-lying land surrounded by higher ground
11
Goods brought in from another country