41.巧妇难为无米之炊 If you have no hand you can't make a fist. One can't make bricks without straw.
42.千里之行始于足下 a thousand-li journey begins with the first step——the highest eminence is to be gained step by step
43.前事不忘后事之师 Past experience， if not forgotten， is a guide for the future.
44.前人栽树后人乘凉 One generation plants the trees in whose shade another generation rests.One sows and another reaps.
