Amphibians are one of the classes of vertebrate animals, and the word "amphibians" is composed of two words, the word "land" and the word "water." Therefore, what is meant by it is that the animal spends part of its life in water, during which it breathes with gills as fish do... As for the other half He spends it on land, and breathes it through his lungs.
In fact, the word "amphibians" - despite its popularity - is considered inaccurate from a scientific standpoint, because these animals are distinguished by the fact that their larval stage depends on gills for breathing, while in their adult stage they breathe through lungs... regardless of the place in which these animals live, Some of them spend their entire lives in the water and do not come to land, and some of them spend most of their lives on land, and only enter the water occasionally. Perhaps it would be more appropriate to call them "biliferous animals". This matches the concept of their common scientific name, "Amphibia".