横向
1
Goods brought in from another country
4
Region surrounding the North Pole
6
Body of water surrounded by land
7
Wearing away of land by water or wind
8
Cold treeless Arctic plain
10
Mountain that can erupt with lava
13
Large area covered with trees
15
Flat grassland in tropical regions
纵向
2
One of seven major landmasses
3
Ocean between Americas and Europe/Africa
5
Total number of people in an area
9
Physical features of land
11
Land surrounded by water on three sides
12
Large slow-moving mass of ice
14
Goods sold to another country