What do actors need to know about writing a play? I think it is helpful if they know enough about playwriting to understand what their job as actors are. First and foremost, a play is NOT conversation. A play is "an imitation of an action" as Aristotle noted. That means that it is something that happens because the characters in the story have emotional and physical reactions to what is going on. These reactions are recorded as the dialog. Yes, what the characters are saying are their emotional and physical responses to the things that are happening around them. Thus the actor needs to be able to present the dialog as his emotional and physical responses to what is happening in the scene. To put a play on paper, a playwright (or screenwriter) does these things.First he creates a scenario by telling the story moment by moment by what happens in the story (NOT what the characters say, ONLY what they do). This is the tricky part, learning to tell a story without any talking going on. It is like an actor learning to do great pantomime. They also want to make sure that what is happening is all ACTIVE and not passive. In other words, they want to make sure that the characters are doing things, not having things done to them. It is better to write "The witch turns the Prince into a frog," than to write "The prince is turned into a frog." The reason for this is that it keeps the play centered in what the characters are doing and that is the essence of a play, what the characters DO and ARE DOING. Once they have the scenario, they go back to the beginning and start translating the actions into the dialog. They use stage directions sparingly. They see the play occur in their mind's eye and hear in their mind's ear what the characters sound like while they write down the characters' reactions as dialog.. The actor works in reverse from the playwight. The actor takes the dialog and translates it back to the emotions and actions it represents. He does that by responding emotionally, using the dialog to verbalize his response, to the stimuli in each moment of the scene.