Structure Tragedy has a characteristic structure in which scenes of dialogue alternate with choral songs. Most tragedies begin with an opening scene of expository dialogue or monologue called a prologue. After the prologue the chorus marches into the orchestra chanting the parodos . Then follows a scene of dialogue called an episode, which in turn is followed by the first stasimon. The exodos is in general a scene of dialogue, but, as in the case of episodes, sometimes songs are included, especially in the form of a kommos .
Some tragedies have one more or less episode and stasimon.