Complex sentence: If a customer buys four new Goodyear tires, they are entered into a contest to go up in the blimp, the winner must go to the nearest blimp base to take their flight.
Split into simpler sentences: If a customer buys four new Goodyear tires, they are entered into a contest to go up in the blimp. The winner must go to the nearest blimp base to take their flight.