Wu Collection, Lower Volume Radical: Stone (shí) Character: ku (kū) Kangxi stroke count: 8 Page 827, Entry 18 Broad Rhymes (Guangyun), Collected Rhymes (Jiyun), Dictionary of Rhymes (Yunhui), and Correct Rhymes (Zhengyun): Pronounced ku (level tone). Ku-ku: Exhausted to the extreme. History of the Former Han (Qianhan Shu), Biography of Wang Bao: Laboring the sinews and bones, working diligently all day long. Ru Chun says: The appearance of working diligently. Han Yu, Discourse on Encouraging Study (Jinxue Jie): Diligent and untiring from the beginning of the year to the end. Also from Collected Rhymes (Jiyun): Pronounced jie (entering tone). Same as the character meaning hard rock (ke). The appearance of stone being hard.