横向
1
Person owned as property
4
Medieval land-for-service system
5
Practice of farming and growing food
6
Government by the people
7
Ancient Mesoamerican civilization
9
Armed entry into another territory
纵向
2
Advanced stage of human society
3
Deadly epidemic disease
8
Long and distinct period of history
10
Handwritten historical document
11
Metal that replaced bronze in tools
12
Movement of people to new areas
13
Freedom from outside control