Complex sentence: Fallacies of composition are probably the essential apsect of a macroeconomic model, because they account for the difference between microeconomics and macroeconomics-without any fallacies of composition there would be no difference between micro and macro models.
Split into simpler sentences: Fallacies of composition are probably the essential apsect of a macroeconomic model, because they account for the difference between microeconomics and macroeconomics. Without any fallacies of composition there would be no difference between micro and macro models.