Complex sentence: A garbage disposal unit or waste disposal unit is a device, usually electrically powered, installed under a kitchen sink between the sink's drain and the trap which shreds food waste into pieces small enough--generally less than--to pass through plumbing.
Split into simpler sentences: A garbage disposal unit or waste disposal unit is a device, usually electrically powered, installed under a kitchen sink between the sink's drain and the trap. The disposal unite shreds food waste into pieces small enough--generally less than--to pass through plumbing.