横向
1
Ocean between Americas and Europe/Africa
5
Ridge of rock or coral near the surface
6
Largest ocean on Earth
8
Area where water covers the soil
纵向
2
Low area between mountains
3
Landform where river meets the sea
4
One of seven major landmasses
6
Land surrounded by water on three sides
7
Cold treeless Arctic plain
9
Wearing away of land by water or wind