How has Chaucer altered the traditional plot of this old tale?

What really stands out is that he has given the animals human characteristics. The Priest tries to ridicule the Prioress and to make that possible Chaucer makes some adjustments. Chauntecleer is no longer just a proud and stupid animal who deserves his fate. He is an intelligent rooster with many virtues. Later we read that the Priest himself looks somewhat like a bird, so he is using the rooster to make himself look good. Pertelote is very much like the Prioress: the prominent hen among equals (nuns). Furthermore the Priest calls Pertelote courteous, discreet and debonaire; very much like the description of the Prioress herself.

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