Surely you didn't do it, did you?／Don't tell me you did it!
I can't possibly tell him to his face that he's a fool, can I?
I (had) never dreamed that I might win (the) first prize.
“I hit him.” “ 「You can't mean it! [You didn't!]”
Go to your uncle in time of need.
I am prepared [ready] for 「whatever may happen [any emergency].