Complex sentence: Presumed dead, the medic sergeant wrapped his body within a sheet of rush mat and left him in the wilderness, where a low-ranking crew member found and tended to him for three days until he regained consciousness.
Split into simpler sentences: Presumed dead, the medic wrapped his body in a sheet of rush mat and left him in the wilderness. A low-ranking crew member found and tended to him for three days until he regained consciousness.