Complex sentence: Jarvis soon becomes lost in the tunnels, and hours or days pass before he and Tweel find themselves in a domed chamber near the surface where the cart creatures desposit their loads beneath a wheel that grinds the stones and plants into dust.
Split into simpler sentences: Jarvis soon becomes lost in the tunnels, and hours or days pass before he and Tweel find themselves in a domed chamber near the surface. There they find the cart creatures despositing their loads beneath a wheel that grinds the stones and plants into dust.