In the second stage (#2), the clouds rise higher and higher because heat is released as the water vapor in the air condenses.
(the clouds; rise; higher and higher; because heat is released as the water vapor in the air condenses; L:In the second stage) (heat; is released; as the water vapor in the air condenses)
the clouds heat
rise is released
higher and higher because heat is released as the water vapor in the air condenses L:In the second stage
as the water vapor in the air condenses