Task: Question Generation
Input (English):  George Monroe, an architectural model fabricator, is fired when he refuses to use computer technology. At his boss's refusal to let George keep a few models, he destroys all but one of the models with a spindle from an architectural drawing,. As he exits the building with the remaining model, he collapses and is rushed to the hospital, where it is revealed he has advanced stage cancer and any treatment would be futile.
George decides to demolish the home left by his father and replace it with a house in keeping with the neighborhood. He enlists his son, Sam, who is alienated from his stepfather Peter and his mother Robin. Sam must spend the summer with George, who has not revealed his terminal condition, and help him with the house, but Sam makes it a point not to help him. When George refuses to give Sam money unless he works for it, Sam toys with becoming a male prostitute, but is nearly caught and flees from his first encounter. This leads him to steal George's Vicodin.
George slowly reconnects with Sam. Robin decides to assist as well, and she finds herself rediscovering George. Also joining in the construction are Alyssa, Sam's classmate who lives next door with her mother Colleen; local policeman Kurt Walker, George's childhood friend; Sam's young half-brothers Adam and Ryan; various neighbors; and eventually Peter, even after separating from Robin when she tells him that her feelings for George have re-awakened. George tells Robin of his disease, sending her into shock. George tells Sam, who is betrayed and accuses George of being selfish and takes refuge at Alyssa's house. George collapses and is found by Robin the following morning. Complications arise when neighbor David Dokos tries to halt construction because the building's height exceeds the allowable limit by six inches. His plans to halt the project are stopped by Sam, who recognizes him from his prostitution attempt and blackmails him.
Sam puts Christmas lights all over the unfinished house and shows George the gleaming house from his hospital window. The next morning, Sam returns to finish the house and Robin sits beside George until his death. Robin goes to the house and tells Sam about his father's death. Sam inherits the house he finished building. Sam gives the property to a woman who has been living in a trailer park. As a girl, she was injured in a car crash caused by his grandfather.
Output (English): What does Sam blackmail David with?