an era is a span of years that might be named for a particular trend or pattern of events.  

a time span lasting 100 years 

a time span of ten years 

the order of events in relation to other events 

the order of events by date 

to tell what might happen in the future 

an event that can be observed 

a document or an object written or created during the time of an event 

a document or an object that analyzes a primary source 

a preference that prevents fair judgment 

a natural feature of the land 

general weather pattern of a place over time 

of or about the city 

of or about the countryside1

likely; possible 

physical location of a place 

location of a place in relationship to other places or features 

something that exists as its own unit; anything that is real 

the structure of a population according to age 

the speed at which a population grows 

a form of government in which power is divided between the federal, or national, government and state governments 

a form of government run by elected representatives 

voters hold sovereign power through elected representatives 

the right to give commands and use power 

rule by the people 

having the power to make laws 

having the power to enforce and carry out laws 

having the power to interpret and apply laws 

a person who legally belongs to a country and has full rights and protections of that country 

an economic system in which people and businesses are mostly free to make their own choices in producing and exchanging goods and services, with limited government interference 

the traditions, beliefs, language, and arts of a particular group 

a variety; a mixture 

to permanently move to a new country 

to separate; to note a difference between 

a group organized by shared characteristics 

a statement based on general truth or knowledge 

a conclusion made based on what is not stated, but implied 

presenting another person’s work as one’s own, whether unintentionally or intentionally 

a credit mentioning the author or artist of a work 

a formal listing of a source