横向
1
Medieval land-for-service system
4
Ancient Egyptian ruler
5
Metal that replaced bronze in tools
6
Ancient Mesoamerican civilization
7
Exchange of goods between peoples
9
Union formed for mutual benefit
纵向
2
Legislative body in ancient Rome
3
Government ruled by a king or queen
8
Sudden overthrow of a government
10
Long and distinct period of history
11
Government elected by the people