noun, noun or participle which takes 'suru'
dumbfounded after a single reading
Describes the state of being so shocked or astonished by what one has read that one is left speechless. Often used in literary or emphatic contexts.
その手紙を一読呆然とした。
I was dumbfounded after reading that letter.
報告書を一読呆然、しばらく言葉が出
After a single reading of the report, I was dumbfounded and couldn't speak for a while.