Complex sentence: His wife finally begs him to tell her his secret, and he explains that he is a werewolf, and that he needs to hide his clothing in a safe place to transform back to human form, a hollow rock.
Split into simpler sentences: His wife finally begs him to tell her his secret, and he explains that he is a werewolf. He explains also that while in werewolf form he needs to hide his clothing in a safe place to transform back to human form in a hollow rock.