When the Earth formed 4.6 billion years ago, a great number of volcano explosions occurred. The volcanic eruption created vapors. Vapors became water drops due to cooling by cold air. The water drops formed into a water mass and grew bigger. These became rain drops and fell into the earth surface. These are known as rain. Then the early-rain created water bodies like oceans, rivers and lakes on the surface of the newly-born Earth.
volcanic explosion,
erupting magma
magma solidification,
vapor occurrence
creating cloud and
rain by cooling
making rivers and
oceans