顿口无言

Explanation: Tongue-tied, speechless. 　　Usage: Joint type; as predicate; describe a loss for words 　　Source: Ming Shinai "Water Margin" 103 back: "Gordon yelled Wang silent mouth, _insert_ candle may also wish to kowtow the sake of convenience." 　　Examples: His remarks, made in the presence of people all ~. Thesaurus:  look at each other in blank dismay, All things stare at each other, Mianmianxiangdan, Mianmianxiangdu