Complex sentence: The book introduces 16-year old Raven Madison, a girl living in Dullsville, who is constantly complaining that there is nothing to do, at least until Alexander Sterling, a vampire, moves in.
Split into simpler sentences: The book introduces 16-year old Raven Madison, a girl living in Dullsville, who is constantly complaining that there is nothing to do. At least, until Alexander Sterling, a vampire, moves in.