Harriet bore the intelligence very well—blaming nobody—and in every thing testifying such an ingenuousness of disposition and lowly opinion of herself, as must appear with particular advantage at that moment to her friend.
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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