横向
1
Low-lying land surrounded by higher ground
3
Visual representation of an area
4
Wearing away of land by water or wind
5
Flat grassland in tropical regions
6
Largest ocean on Earth
8
One of seven major landmasses
10
Height above sea level
纵向
2
Total number of people in an area
3
Seasonal heavy rainfall
7
Body of water surrounded by land
9
Goods sold to another country