a type of shark that sucks food off the sea floor at night and does not move around much from place to place

Nurse sharks are a docile species who spend much of their time lying on the bottom. 护士鲨是一种温顺的动物，大部分时间都躺在海底。

Most nurse shark attacks happen when a diver pulls the shark's tail. 大多数护士鲨只有在潜水员拉动其鲨鱼尾巴的时候才会发起攻击。