However often she told herself that she must not get irritable when teaching her nephew, almost every time that, pointer in hand, she sat down to show him the French alphabet, she so longed to pour her own knowledge quickly and easily into the child—who was already afraid that Auntie might at any moment get angry—that at his slightest inattention she trembled, became flustered and heated, raised her voice, and sometimes pulled him by the arm and put him in the corner.
… Dron Zakharych, you!" meek and flustered voices here and there were heard calling and caps began to come off their heads.
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He gets flustered when talking to groups and tends to lose his train of thought.