横向
1
Exchange of goods between peoples
4
Freedom from outside control
5
Metal that replaced bronze in tools
6
Period of ten years
7
Object made by humans from the past
8
Government elected by the people
纵向
2
Practice of establishing foreign colonies
3
Person who travels to discover new lands
6
Succession of rulers from same family
9
Person with no fixed home
10
Armored warrior of medieval times
11
Legislative assembly of a country
12
Long and distinct period of history