横向
1
Physical features of land
5
Chain or group of islands
6
Flat grassland in tropical regions
8
Largest ocean on Earth
9
Ridge of rock or coral near the surface
11
Large body of water partly enclosed by land
纵向
1
Cold treeless Arctic plain
2
Mountain that can erupt with lava
3
Large slow-moving mass of ice
4
Wearing away of land by water or wind
7
Long-term weather patterns of an area
10
Body of water surrounded by land
12
Largest river in South America