牛角挂书 niújiǎoguàshū to be diligent in one's studies Origin Definitions Defs Strokes Stroke Words Sentences Sents 牛角 niújiǎo ox horn the horn of a cow or ox挂 掛 guà verb to hang to hang; to suspend; to hitch; to be snagged or caught on something书 書 shū noun book book; volumes or works of text or drawings bound together