Mao Collection, Upper Volume Radical: Heart (xīn) Character: Xu Kangxi strokes: 8 Page 378, Entry 02 Broad Rhymes (Guangyun) and Collected Rhymes (Jiyun) state: pronounced yu (falling tone). Collected Rhymes (Jiyun) states: to advance, to be at ease. Originally written as yu. Sometimes written in a variant form as xu. Commonly written as yu. Also, Supplementary Dictionary (Zihui bu) states: same as shu (to stretch).