Complex sentence: She supplemented this work with various supporting cast roles on TV including "Citizen Smith" and "Doctor Who" in 1979, Christmas pantomimes and dancing on cruise liners; before she took a job in a cabaret show in Hong Kong, dancing and singing.
Split into simpler sentences: She supplemented this work with various supporting cast roles on TV including "Citizen Smith" and "Doctor Who" in 1979, Christmas pantomimes and dancing on cruise liners. She then took a job in a cabaret show in Hong Kong, dancing and singing.