深不可测

Explanation: Won can not be measured. Compared the situation of things unpredictable. 　　Usage: Partial official; as predicate, attributive, adverbial; compared the situation of things unpredictable 　　Source: Han Liu, "Huainanzi primary surgery training": "Heaven mysterious silent, no content is free, not very large, unfathomable." 　　Examples: Long Emperor ~ smile. (China and the real "Chinese Dress" a) 　　Riddle: Bottomless pit Thesaurus:  not know why it is so, intangibility, extremely puzzled; be completely confused, mystery of mysteries— — extremely mysterious and abstruse, Figure it out, Puzzling, Up on things vain, Couldn't find north, Touch door vain, cannot distinguish whether it's genuine or fake,true or false, perplex Antonym Group:  deafening noise, Fakuizhenlong