exposition

Confident writers parse out exposition, bit by bit, through the entire story, often revealing exposition well into the Climax of the last act. They follow these two principles: Never include anything the audience can reasonably and easily assume has happened. Never pass on exposition unless the missing fact would cause confusion. 
例子：In THE LAST EMPEROR a man spends his life trying to answer the question: Who am I? At age three Pu Yi is made Emperor but has no idea what that means. To him a palace is a playground. He clings to his childhood identity until as a teenager he’s still nursing from the breast. The Imperial officials insist he act like an emperor, but he then discovers there is no empire. Burdened with a false identity, he tries on one personality after another but none fit: first English scholar and gentleman; then sex athlete and hedonist; later international bon vivant doing Sinatra imitations at posh parties; next a statesman, only to end up a puppet to the Japanese. Finally, the Communists give him his last identity—gardener. 
FAREWELL, MY CONCUBINE（霸王别姬） tells of Dieyi’s (Leslie Cheung) fifty-year quest to live in the truth. When he is a child, the masters of the Peking Opera ruthlessly beat, brainwash, and force him to confess that he has a female nature—when he does not. If he did, torture wouldn’t be necessary. He’s effeminate, but like many effeminate men he is at heart male. So, forced to live a lie, he hates all lies, personal and political. From that point on all the conflicts in the story stem from his desire to speak the truth. But in China only liars survive. Finally realizing that truth is an impossibility, he takes his own life. Because lifelong Spines are rare, we take Aristotle’s advice to begin stories in medias res, “in the midst of things.” After locating the date of the climactic event of the protagonist’s life, we begin as close in time to it as possible. This design compresses the telling’s duration, and lengthens the character’s biography before the Inciting Incident.
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