横向
1
Government by the people
7
Metal that replaced bronze in tools
8
Deadly epidemic disease
9
Medieval land-for-service system
10
Large territory under one ruler
11
Military blockade of a fortified place
12
Union formed for mutual benefit
纵向
2
Person who travels to discover new lands
3
Alloy of copper and tin used in early tools
4
Period of one hundred years
5
Medieval religious military campaign
6
Territory controlled by another country
13
Advanced stage of human society