亡羊补牢,为时不晚: It’s never too late to mend.
甲之蜜糖,乙之砒霜:One's meat is another's poison.
以牙还牙,以眼还眼:one eye for one eye
金无足赤,人无完人: No one is perfect
王婆卖瓜,自卖自夸: blow one's own trumpets
九牛一毛,沧海一粟:a drop in a bucket
无功不受禄: can't take the credit for nothing
拆东墙补西墙: rob Peter to pay Paul
万事开头难:It is the first step that is troublesome
千里之行,始于足下:A journey of a thousand miles begins with a single step.