If I was stuck on an island and only had three items I would want to have a large knife, loads of duck tape, and a magnifying glass. I would want the knife to make spears and traps to catch my food. I could kill people if they attack me or a wild animal does. I would use it to help build my shelter as well. I would use the magnifying glass to make a fire to keep me warm and cook my food on. I would need it to make a signal fire as well. I would use the duck tape to put my traps together, help build a shelter, make a hammock, and use it for a help sign so that people sailing or flying by will see it and rescue me. I would also use it to make a water pouch to keep fresh water in. I would also need it to taping animals or people up so they can't get me. I would use the ducktape and knife to make a boat and sail somewhere else. I'd use the knife and some ducktape to make a fishing pole for when I'm in the boat. I would also use my materials to make a top over the boat invade it rains.