◎ 批郤導窽 pīxì-dǎokuǎn

[make penetrating criticism(like carving joints by skillful butcher);hit the nail on the head] 《莊子·養生主》:“依乎天理,批大郤,導大窽,因其固然。”在骨頭接合的地方批開,沒有骨頭的地方則就勢分解。比喻抓住關鍵,事情就能順利解決