Complex sentence: Ashton Kutcher did not renew his contract for the eighth and final season of the series, he appeared in a recurring guest role in the first four episodes of Season 8 in order to bring closure to the character.
Split into simpler sentences: Ashton Kutcher did not renew his contract for the eighth and final season of the series. Kutcher appeared in a recurring guest role in the first four episodes of Season 8 in order to bring closure to the character.