行家里手

Explanation: Li Shou: insiders. Refers to the person versed in this business. 　　Usage: Joint type; as predicate, object; that people proficient in this business 　　Source: Qing Wu Jian "Twenty years Strange": "what's wrong with criticism, saying that the source of the thing, indeed, is a connoisseur." Thesaurus:  sage; wise man, Chop wheel adept, professional training class origin, Break Well-established