what is its poetic structure?
The poem is made up of 18 stanzas of six lines each.
The Raven
The poem is made up of 18 stanzas of six lines each. 
summary of the raven by edgar allen poe It tells of a talking raven's mysterious visit to a distraught lover, tracing the man's slow fall into madness. The lover, often identified as a student, is lamenting the loss of his love, Lenore.
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The Raven [SEP] Poetic structure
The poem is made up of 18 stanzas of six lines each. Generally, the meter is trochaic octameter – eight trochaic feet per line, each foot having one stressed syllable followed by one unstressed syllable. The first line, for example (with / representing stressed syllables and x representing unstressed): Poe, however, claimed the poem was a combination of octameter acatalectic, heptameter catalectic, and tetrameter catalectic. The rhyme scheme is ABCBBB, or AA,B,CC,CB,B,B when accounting for internal rhyme. In every stanza, the "B" lines rhyme with the word "nevermore" and are catalectic, placing extra emphasis on the final syllable. The poem also makes heavy use of alliteration ("Doubting, dreaming dreams ...").