横向
1
Low-lying land surrounded by higher ground
4
Region between the two tropic lines
5
Seasonal heavy rainfall
6
Large area covered with trees
7
Deep narrow valley with steep sides
11
Land surrounded by water
13
Total number of people in an area
纵向
2
Large natural elevation of earth
3
Long-term weather patterns of an area
8
Mountain that can erupt with lava
9
Land surrounded by water on three sides
10
Landform where river meets the sea
12
Largest ocean on Earth