横向
1
Flat grassland in tropical regions
4
Line dividing two countries
7
Cold treeless Arctic plain
8
Region between the two tropic lines
9
Goods sold to another country
11
Long-term weather patterns of an area
纵向
2
Tool for finding directions
3
Mountain that can erupt with lava
5
Area where water covers the soil
6
One of seven major landmasses
10
Deep narrow valley with steep sides
12
Vast body of salt water
13
Large area covered with trees