刻苦钻研 kèkǔzuānyán to study diligently Definitions Defs Origin Strokes Stroke Words Sentences Sents 刻苦 kèkǔ adjective hardworking hardworking; assiduous; painstaking; willing to put in hard work and endure hardship钻研 鑽研 zuānyán to study intensively To study meticulously or delve into a subject with great depth and focus.