横向
1
Low-lying land surrounded by higher ground
4
Total number of people in an area
5
Large area covered with trees
7
Region near the equator
8
Distance north or south of equator
10
One of seven major landmasses
纵向
2
Height above sea level
3
Deep narrow valley with steep sides
6
Large body of water partly enclosed by land
9
Largest ocean on Earth
11
Raised area of land, smaller than a mountain
12
Vast body of salt water