introductions

to tell a story that makes a point

to give background on people or event

to show sequence of events

to show steps of action

to explain how to do something

to clarify a point or concept

to give a picture or specific instance

to make the abstract real

to compare scenarios

to compare to a settled outcome

to compare one event to another very different one

to clarify meaning

to set foundation of argument

to give background

to draw distinctions between items

to find common ground

to give details

to create a picture

to lead from one item to another

to argue logic of evidence of action

to put items in categories

to clarify comparison of items in a category

to divide items by characteristics