英语翻译早在有恐龙之前就已经有鲨鱼了 他是海洋中最凶猛的动物鲨鱼非常的大并且有像锯齿一样尖尖的牙鲨鱼有一身软骨,软骨比骨

Sharks existed long before there were dinosaurs.
They are the fiercest animals in the ocean.
Sharks are large creatures with sharp saw-like teeth.
Sharks have soft cartilage throughout their entire body,which provides greater flexibility than skeleton.
Sharks have to continuously swim about,otherwise they'll suffocate.