横向
1
Movement of people to new areas
2
Metal that replaced bronze in tools
6
Long and distinct period of history
7
Exchange of goods between peoples
8
Person owned as property
10
Payment made to show submission
11
Object made by humans from the past
12
Roman arena fighter
纵向
2
Freedom from outside control
3
Government by the people
4
Military conflict or fight
5
Ancient Egyptian picture writing
9
Military blockade of a fortified place
13
Ancient Mesoamerican civilization