Complex sentence: Making matters worse, Donna's Ford Pinto car's alternator dies, meaning the two can't leave, so they are forced to stay inside the Pinto while Cujo waits outside, attacking repeatedly, all while Vic is out of town on a business trip.
Split into simpler sentences: Making matters worse, Donna's Ford Pinto car's alternator dies, meaning the two can't leave. So they are forced to stay inside the Pinto while Cujo waits outside, attacking repeatedly, all while Vic is out of town on a business trip.