The USA
作者：Michael John Varney
1. Nature & climate
1.1. climate variations and zones
1.2. animal life
1.3. plantlife
1.4. weather extremes
2. people
2.1. population
2.2. ethnicity
2.3. 50 states
3. Constitution
3.1. Government form
3.1.1. Republic
3.1.2. Federal & State
3.2. Congress
3.2.1. House of Representatives
3.2.2. Senate
3.3. The president
3.4. The Supreme Court
4. Geography
4.1. mountain ranges
4.2. location and boundaries
4.3. Natural wonders
4.3.1. Fx Grand Canyon
4.4. Cities
4.4.1. famous landmarks
4.4.2. New York
4.4.3. Los Angeles
4.4.4. San Francisco
4.4.5. Washington
5. History
5.1. Independence
5.2. Early colonisation
5.3. Native americans
5.4. Civil War
5.5. African American history
5.6. modern times
6. Culture
6.1. Music
6.1.1. hip hop
6.1.2. jazz