The shark's skin isn't covered with scales, like other fish: instead the skins covered with barbs, giving it a rough texture like sandpaper.
鲨鱼的皮肤不像其他鱼类一样由鳞覆盖。相反，它的皮肤布满了倒钩，形成砂纸一样的粗糙质地。
As you know, sharks are very quick swimmers.
如你所知，鲨鱼是游泳健将。
This is made possible by their fins, one set at the side and another set underneath the body, and the tailalso helps the shark move forward quickly.
这归功于它的鳍，一组在一侧，另一组在身体下面，尾巴也帮助鲨鱼快速的向前移动。
Unlike other fish, sharks have to keep swimming if they want to stay at a particular depth, and they rarely swim at the surface.
与其他鱼类不同，如果鲨鱼想停留在某一特定的深处就得不停的游，它们很少在海面游。
Mostly, they swim at the bottom of the ocean, scavenging and picking up food that’s lying on the ocean floor.
多数情况下，它们在海底游弋，搜寻捕食海底的食物。
While most other animals, including fish, hunt their prey by means of their eyesight, sharks hunt essentially by smell.
多数动物，包括鱼类都用它们的视力捕食，而鲨鱼基本上靠嗅觉。
They have a very acute sense of smell - and can sense the presence of food long before they can see it.
它们的嗅觉十分敏锐，可以探测到视力范围很远以外的食物。