0 a large wheel that is turned by flowing water and used to provide the power for machinery -- (为机械提供动力的)水轮,水车
We can complete it step by step however long the road is and it can't be completed however short the road is if you don't even mark your footprint.
再长的路,一步步也能走完,再短的路,不迈开双脚也无法到达。