hóng / máo / Tài / Shān / zhè / gè / chéng / yǔ / bǐ / yù / qīng / zhòng / chā / bié / jí / dà

鸿毛泰山这个成语比喻轻重差别极大。

The idiom 'feather and Mount Tai' describes an extreme difference in importance.