Most Greek tragedies have a fairly standard structure. There are actually two ways you can divide a Greek tragedy into parts, one by literary form and one by type of action. Literary critics use both sets of terminology.
1. Prologue -- spoken by characters before the chorus enters
2. Parados (entrance song) -- sung by the chorus as it first enters
3. Episode -- discussions among the 2-3 individual actors. A play is composed of several episodes.
4. Stasimon (standing song): Between episodes, the chorus dances and sings choral odes in the area known as the orchestra (Greek for "dancing place")
5: Exodos (leaving song): sung chorus sings while leaving
Some critics divide the action of a play can be divided into exposition, rising action, climax, falling action, and dénouement, although not all plays fit this structure precisely.