Original sentence: Adding to their fright is that they don't even know what is behind the kills, whether it is a man or an animal or something else.. The remaining fearful crew members struggle to survive invisible entity which is stronger, smarter and faster than them
Edited sentence: Adding to their fright is that they don't even know what is behind the kills, whether it is a man or an animal or something else.. The remaining fearful crew members struggle to survive the invisible entity which is stronger, smarter and faster than them