1.Amazon is the (longest) river in the world. 2. The Amur is the (longest) river in Russia. 3. The Amazon is (longer) than the Amur. 4. Everest is the (highest) mountain in the world . 5.The great white shark is the most (dangerous) shark. 6.The blue whale is much (larger) than the great white shark. 7.Dolphins much more (clever) than sharks.