Complex sentence: The pneumonia he contracts is a mutated strain and, while delirious, he has three hallucinations which become solid: fish rain in his sleeping quarters; the Mayor of Warsaw spontaneously combusting; and two guests who materialise in the drive room.
Split into simpler sentences: The pneumonia he contracts is a mutated strain and, while delirious, he has hallucinations which become solid. Fish rain in his sleeping quarters, the Mayor of Warsaw spontaneously combusts and two guests materialise in the drive room.