astonish + -ing

source: JoJo - Yes I Am ! ［HD］ on Make a GIF

extremely surprising or impressive; amazing:

(その意外性により)〈事･人･物が〉〈人〉を非常に驚かす, 仰天させる(amaze); 〖it ～es A that節〗 …ということがA〈人〉を仰天させる

e.g. an astonishing achievement

e.g. I find it astonishing that they ever thought it could work.