金玉其表，败絮其中
jīn​yù​qí​biǎo​bài​xù​qí​zhōng

fair without but foul within

  1. 金玉 jīn​yù
    gold and jade
    gold and jade; precious metals and stones; treasures or beautiful things
  2. 其 qí pronoun
    [third-person possessive]
    his; her; its; their; refers back to a person or thing mentioned previously
  3. 表 biǎo noun
    surface
    (bound form) surface; exterior; outside
  4. ， bài
    non-Chinese
  5. 败絮 敗絮 bài​xù
    waste cotton
    ruined cotton padding; metaphorically used to describe something or someone that is useless or rotten on the inside (as in the idiom 'gold and jade on the outside, rotten cotton inside')
  6. 其中 qí​zhōng pronounpreposition
    among them
    among; in; included in a group or situation already mentioned