Complex sentence: Clark is reminded of an earlier incident where Eddie had been dumping sewage into a storm drain, but before he can do anything, Uncle Lewis tosses his match aside, which causes an explosion, sending him flying and the entire family to the ground.
Split into simpler sentences: Clark is reminded of an earlier incident where Eddie had been dumping sewage into a storm drain. But before he can do anything, Uncle Lewis tosses his match aside, which causes an explosion that sends him flying and the entire family to the ground.