Complex sentence: Regenerative cooling is a method of cooling gases in which compressed gas is cooled by allowing it to expand and thereby taking heat from the surroundings, the cooled expanded gas then passes through a heat exchanger where it cools the incoming compressed gas.
Split into simpler sentences: Regenerative cooling is a method of cooling gases in which compressed gas is cooled by allowing it to expand and thereby taking heat from the surroundings. The cooled expanded gas then passes through a heat exchanger where it cools the incoming compressed gas.