Recurring expressions and idiolectal speech patterns are often used by the scriptwriters of sitcoms to portray the personality of some of the characters. These expressions, which in many cases end up becoming popular, are so significant that they need be kept in the translated versions of these series. A corpus-based script analysis method that detects these recurring expressions and idiolectal speech patterns semi-automatically has been successfully tested in a professional environment. It has also been piloted in a translation classroom twice in the form of a task-based teaching unit consisting of four tasks: a preliminary task, two analyses or pre-translation tasks and one final translation task. In this article we: (1) describe typical AVT trainer profiles; (2) comment on publications dealing with corpus-based AVT training; (3) explain a corpus-based script analysis method designed to optimise time, effort, resources and coherence when translating multi-season series; and (4) present the corpus-based teaching unit, including task sheets and a tutorial, plus the results of a questionnaire study carried out after the implementation of the method described.