The onomatopoeia used are WHISTLES and WHINING....
Whining school boy; sighing like furnace; whistles in his sound ;
In "The Seven Ages of Man," Shakespeare uses onomatopoeia through words like "whining," "sighs," and "whistles" to create vivid imagery. These words imitate sounds that reflect the emotions of the characters, especially the schoolboy. This use of sound words enriches the poem's description and emotional impact.
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