good gracious
US /ɡʊd ˈɡreɪ.ʃəs/
UK /ɡʊd ˈɡreɪ.ʃəs/

1.
あらまあ, まさか
an exclamation of surprise, alarm, or exasperation
:
•
Good gracious, I completely forgot about our appointment!
あらまあ、約束をすっかり忘れてたわ!
•
Good gracious, look at the mess you've made!
あらまあ、なんて散らかしたの!