1. Vocabulary
Mesopotamia

2. Geographical location
specific physical point on Earth. This is more precise than "area" defined by latitude and longitude.

3. politics
the activities of governments concerning the political relations between countries.

4. people living together in a more or less ordered community.
 society
people living together in a more or less ordered community.

5. the state of being scarce or in short supply.
scarcity
the state of being scarce or in short supply.

6. Mesopotamia
 An ancient region of SW Asia in present- day Iraq, lying between the Rivers Tigris and Euphrates. Its fertile plains were the site of the civilizations of Akkad, Sumer, Babylonia, and Assyria.

7. natural disasters
a natural event such as a flood, earthquake, or hurricane that causes great damage or loss of life.

8. river valley
lowland between ranges of mountains, hills, or other uplands, often having a river or stream running along the bottom.

9. Silt
fine sand, clay, or other material carried by running water and deposited as a sediment.

10.  irrigation
is the method in which water is supplied to plants. It is used to assist in the growing of crops. In dry areas and during periods of not enough rainfall.

11. an amount of something left over
surplus
an amount of something left over

12. a city that with its surrounding territory forms an independent state.
city-state
a city that with its surrounding territory forms an independent state.

13. the belief in or worship of more than one god.
polytheism
the belief in or worship of more than one god.

14. a rectangular stepped tower, sometimes surmounted by a temple.
ziggurat
 a rectangular stepped tower, sometimes surmounted by a temple. 

15. relating to the wedge-shaped characters impressed on clay tablets.
cuneiform
relating to the wedge-shaped characters impressed on clay tablets.

16. a person who copies documents
scribe
a person who copies documents

17.  epic
a long poem, from ancient oral tradition, narrating the adventures of heroic or legendary figures or a nation.

18. an extensive group of states or countries under a single authority.
empire
an extensive group of states or countries under a single authority.

19. tribute
an act, or gift that is intended to show gratitude, respect, or admiration.

20. a principal administrative division of certain countries or empires
province
a principal administrative division of certain countries or empires

21.  caravan
a group of people, especially traders or pilgrims, traveling together across a desert in Asia or North Africa.

22. an expert in or student of astronomy.
astronomer
an expert in or student of astronomy.

23. isthmus
a narrow strip of land with sea on either side, forming a link between two larger areas of land.

24.  maize
technical or chiefly

25. sinkhole
caused by water erosion and providing a route for water to disappear underground.

26.  industry
economic activity concerned with the processing of raw materials and manufacture of goods in factories

27. all the inhabitants of a particular town, area, or country.
population
all the inhabitants of a particular town, area, or country.

28. ecosystem
a biological community of interacting organisms and their physical environment.

29.  family
a group consisting of parents and children living together in a household

30. ethnic
of or relating to a population subgroup (within a larger or dominant national or cultural group) with a common national or cultural tradition

31. extreme scarcity of food.
famine
extreme scarcity of food.

32. drought
a prolonged period of abnormally low rainfall; a shortage of water resulting from this

33.  resources
a stock or supply of money, materials, that can be used by a person or organization in order to work effectively.