The title of our submarine is The Warrio. The materials that we use are a balloon, a tube, a vitamin bottle, tapes, zap straps and two equal weight rocks. As the picture shows, it has a lot of special places. There are six different holes on the bottle so the water can comes in quickly and the density of the submarine would be higher than 1 g/cm3. The tube is attached with a ballon with a zap strap so when we blow the ballon, the submarine would float on the water. The rocks are surrounded by the tapes so the rock would be very stable. Also, the rocks can help the submarine to sink better. The rocks must be in the middle of the submarine because it can help the submarine to hold the balance, and those two rocks must be the same weight so the submarine won't went down straightly. This is our great submarine- The Warrio.