Mitya went on with the same confiding ingenuousness, drying his face and hands on the towel, and putting on his coat.
Though to laugh at Mitya to his face was rather a risky proceeding, there was much laughter behind his back, especially in the tavern, at his own ingenuous public avowal that all he had got out of Grushenka by this "escapade" was "permission to kiss her foot, and that was the utmost she had allowed him."
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Show samples from other sources
She plays a wide-eyed, ingenuous schoolgirl forced to grow up too quickly.
The face of the old man was stern, hard-featured, and forbidding; that of the young one, open, handsome, and ingenuous.
Dickens, Charles -- The Life and Adventures of Nicholas Nickleby