Had Avdotya Romanovna been dressed like a queen, he felt that he would not be afraid of her, but perhaps just because she was poorly dressed and that he noticed all the misery of her surroundings, his heart was filled with dread and he began to be afraid of every word he uttered, every gesture he made, which was very trying for a man who already felt diffident.
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She is diffident around adults, but dominant with her peer group.
At first, he could give no encouragement; with unfeigned diffidence, he expressed his conviction that he was not adequate to the performance of so great a task;
Frederick Douglass -- The Narrative of the Life of Frederick Douglass