【升堂入室】〖shng táng rù shì〗[pass through the hall into the inner chamber -- have profound scholarship; become highly proficient in one's profession; gain the mastery of; reach a higher level in one's studies]

升高行远循渐进，

堂构箕裘温知新。

入理切情熟生巧，

室学勤恳博精深。

比喻学识或技能由浅入深，循序渐进，逐步达到很高的成就。古代宫室，前为堂，后为室。Metaphor knowledge or skills from shallow to deep, step by step, gradually achieve very high achievements. ancient palace room, front is hall, rear is room.同：登堂入室。