横向
1
Armed entry into another territory
5
Medieval land-for-service system
6
Person owned as property
7
Uprising against authority
9
Metal that replaced bronze in tools
10
Large territory under one ruler
纵向
2
Ancient empire that conquered much of Europe
3
Military blockade of a fortified place
4
Military conflict or fight
8
Person who travels to discover new lands
11
Succession of rulers from same family
12
Advanced stage of human society