doubted, suspected, realized
Je ne me doutais pas que je me faisais arnaquer.
I had no idea I was being scammed.
C'est toi qui doutais de la perfection de son corps.
You were the one who doubted the perfection of her body.
— Funny Games (1997)
Tu en doutais ?
Did you doubt it?
— Moscou ne croit pas aux larmes (1980)
Tu ne te doutais de rien ?
You didn't suspect a thing?
— The Umbrellas of Cherbourg (1964)
Je ne doutais pas que mon père viendrait.
I had no doubt that my father would come.
Je ne me doutais de rien.
I had no idea.
Mais tu t'en doutais.
But you already suspected as much.
— Tesis (1996)