1.there are than 350 different kinds of sharks, such as the great white and whale sharks (many) 2.fossils show that sharks for 420 million years , since the early silurian (exist) 3.the fins of for stabilizing,steering , lifting and swimming(use) 4.some new kinds of sharks over the past ten years (find) преобразуйте слова чтобы они грамматически подходили содержанию текста