Why amphibians live near water or in a moist environment?

amphibians are those kind of animals,which couldnt leave without water ,and they also cant breath in water too long,so they need to come out on ground. they need to be clother to the water because they eat water insects, fishes,some kind of plants and so on, which are important for them. if they couldnt find food on ground,they are going into the water.