Complex sentence: Smith became best known through his portrayal of Harold Bishop in the soap opera "Neighbours" from 1987 to 1991 and then from 1996 before switching to recurring status from 2008 until 2009, becoming one of its longest serving characters.
Split into simpler sentences: Smith became best known through his portrayal of Harold Bishop in the soap opera "Neighbours" from 1987 to 1991, and returning in 1996. He switched to recurring status from 2008 to 2009, becoming one of its longest serving characters.