紅褲子出身

粵劇用語，指由劇團從低訓練出嚟嘅原班演員，非中途加入嘅外來成員，傳統上呢類演員會穿著紅褲以作識別。 (Jargon of Cantonese Opera, means an actor was trained from the basic and start from the grassroots roles all in the same troupe, not the one that jump in the troupe from outside. Traditionally, these actors would wear red trousers as recognition. Literally:origin of red trousers)

比喻一個人由基層做起、從實際工作中磨練出經驗同技術，而非學院派、理論派，或靠關係上位嘅#黃馬褂。 (Figuratively someone worked from the root, gained technique and experience from practical operation, not the academist, theorist, nor getting the rank by privately related to the boss.)