横向
1
Cold treeless Arctic plain
5
Distance east or west of prime meridian
6
Deep narrow valley with steep sides
10
Imaginary line around the middle of Earth
11
Steep rock face at edge of land
纵向
2
Large slow-moving mass of ice
3
Largest river in South America
4
Goods brought in from another country
7
Goods sold to another country
8
Height above sea level
9
Low area between mountains
12
Region between the two tropic lines