Penjelasan:

Fish live in saltwater and freshwater all over the world. They come in many different shapes and sizes, but most are covered in scales and have strong fins for swimming. A fish's scales all lie in the same direction to help the fish slip through water. Like us, fish need oxygen to live. But instead of breathing air, they absorb the oxygen in water. Water enters the mouth and is swept over the gills. The oxygen passes from the water into tiny blood vessels in the gills. Fish often swim in groups called shoals. One reason they do this is for protection. Many fish together can confuse a predator. This makes it hard for the predator to single out a fish.