How does Chaucer describe the prioress and the monk?
Both the Nun and the Monk are guilty of breaking their vows of poverty and obedience. Both own pets, which would have been considered a luxury. The nun has pet dogs and the monk has greyhounds that he uses for hunting. Keep in mind both of them should have a life dedicated to helping the poor, praying, and working in the abbey or monastary. Both are also dressed better than they should be and both are very well fed.
Chaucer portrays the nun as somewhat of a phony with her manners and her substandard French. He gives this long description of her table manners, but then goes on to say she only appears dignified. He also references her large forehead. During this time period, a broad forehead was thought to be a sign of good breeding and intelligence, but her forehead is huge! Chaucer is exaggerating this feature to poke fun at her belief that she is so dignified and proper. He does say that she is "charitable and pious," but in the next line we find out this is only towards animals.
The monk is shirking his duties in the monastery to go out hunting. He doesn't want to do the studying, as the books make his head spin, and he doesn't want to do the hard physical labor. Instead he is out with his greyhounds hunting. Like the nun, he is well-dressed with fur-trimmed robes and he is wearing a gold pin.
Neither of them are particularly bad people, but they do not take their vows seriously.