Complex sentence: Unwilling to let Ellie die, Joel battles his way to the operating room and carries the unconscious Ellie to the parking garage, where he is confronted by Marlene, whom he shoots and kills to prevent the Fireflies from pursuing them.
Split into simpler sentences: Unwilling to let Ellie die, Joel battles his way to the operating room and carries the unconscious Ellie to the parking garage. He is confronted by Marlene, whom he shoots and kills to prevent the Fireflies from pursuing them.