Complex sentence: The novel takes the form of a letter Ramsay writes to the headmaster of the school from which he has just retired, wherein he recalls how, as a boy, he ducked the fateful snowball intended for him.
Split into simpler sentences: The novel takes the form of a letter Ramsay writes to the headmaster of the school, from which he has just retired. Wherein he recalls how as a boy, he ducked the fateful snowball intended for him.