In the poem "The Raven" how does Poe use motif to create mood?

In “The Raven,” Edgar Allan Poe uses motif to create the mood of melancholy and longing. A motif is a repetitious idea, sound, or image in a piece of literature. Poe repeats the sounds in the words “nothing more,” “evermore,” and “nevermore” at the end of stanzas. The sound of these words mimic “Lenore," the name of the young man’s deceased girlfriend. At the beginning of the poem he is trying to determine who is at his door, and in his sadness he hopes that it is his beloved Lenore, but he looks into the hall and finds nothing. Later in the poem the raven flies in and perches on the bust of Pallas.

The young man tortures himself questioning the raven. The raven was trained by his unknown owner to say “Nevermore.” Even when the young man asks if there will be relief in the end, he receives the same answer.

"Is there—is there balm in Gilead?—tell me—tell me, I implore!" Quoth the Raven, "Nevermore."

Each repetition from the beginning to the end of the poem leads the young man deeper and deep into his sadness.