Mike Chang has appeared on Glee since an episode that premiered on what network?
Mike Chang:  The character is portrayed by actor and dancer Harry Shum, Jr., and has appeared on "Glee" since the fourth episode in the first season, "Preggers", first broadcast on September 23, 2009. Preggers:  The episode premiered on the Fox network on September 23, 2009, and was written and directed by executive producer Brad Falchuk.
Fox