Complex sentence: The force of the impact sent Biggs flying through the windshield and Mallard left Biggs in the car in her garage, did not notify the police, and later, after Biggs died, she left the body in a park.
Split into simpler sentences: The force of the impact sent Biggs flying through the windshield. Mallard placed Biggs in her car, and later left her car in her garage, did not notify the police, and later, after Biggs died, she left his body in a park.