1) Becomes a gully 2) Becomes worn 3) Breaks down 4) Causes detritus 5) Causes wear to 6) Chips away 7) Chips away at 8) Creates a canyon 9) Creates naturally as a gorge 10) Creates ravines 11) Crumbles 12) Crumbles away 13) Crumbles seed or nuts 14) Cuts into 15) Decays gradually 16) Destroys by degrees 1) Eats 2) Eats in to 
to wear away