Complex sentence: At the beach-house, she sees her old friends crowded around Homer's car and when she shouts at them, they show her their handiwork-they have covered the car with sea shells, with one bunch spelling out "Lisa Rules".
Split into simpler sentences: At the beach-house, she sees her old friends crowded around Homer's car, doing something to it. When she shouts at them, they show her their handiwork-they have covered the car with sea shells, with one bunch spelling out "Lisa Rules".