阐明

The report aims at clarifying how the bill was passed.

illustrate/elucidate by facts

elucidate clearly/thoroughly

fully/briefly explain

formulate one's thoughts methodically

illustrate/enunciate a principle

shed light on a point; elucidate/expound/illustrate/interpret a point

throw light on a subject; elucidate/expound/illuminate a subject

set forth the facts

expound the laws of social development

illuminate/illustrate a point; set out/illuminate an argument; drive a point home

make clear/set forth/define one's position; clarify/expound/illustrate one's stand

set out/explain one's reasons

elucidate/expound/explicate a theory; elaborate on a theory

spell out/set forth a plan

set forth/clarify/expound one's views; set out/illustrate one's ideas