At the beginning of the poem, the word "nevermore" is just a response by the raven to the questions of the narrator. However, as the "conversation" continutes, the word becomes an expression of the narrator's own feelings, even though it is still spoken by the bird. The narrator is grief-stricken, and feels that his grief will last eternally. It will "nevermore" go away. The word becomes a symbol of the narrator's internal conflict.
Poe, in "The Philosophy of Composition", explained that grief was his chosen theme in this poem. He chose the word nevermore because of the strong "o" sound, feeling that this particular vowel best expressed a feeling a sadness.
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The word begins as just an amusement to the narrator of the poem - "How clever a bird to be able to say 'nevermore'!" But then the narrator begins to choose questions to ask the bird, hoping to get some sort of different reply. When he doesn't get the answers he wants (the answer is always 'nevermore'), he becomes angry at the bird and despairs over his lost love, Lenore. Finally, the narrator just accepts that his life with Lenore is over - there is no hope for an afterlife existence with her - all because of this bird's limited vocabulary. Check out the link below for more information - Good luck!
To show affection in the story that somthin is taring him a part.