Answer:
The correct words are lungs and skin. The sentence should be:
Frogs breathe through their lungs on land and through their skin in water.
Frogs are amphibians, which means they can live both on land and in water. They have a special type of skin that allows them to absorb oxygen and water through it. This is called cutaneous respiration. However, when they are on land, they need to use their lungs to breathe air. They also have nostrils that help them inhale and exhale air.