Why does the poet repeat the phrase 'nevermore' throughout the poem?

为什么诗人在这首诗中反复使用短语'永不复还'？

同一单元的其他句子

• The poet's imagery evokes a sense of melancholy and longing.诗人的意象唤起了一种忧郁和渴望的感觉。
• She recited the poem with such passion that everyone was moved.她充满激情地朗诵这首诗，感动了所有人。
• Can you identify the rhyme scheme in this sonnet?你能识别这首十四行诗的押韵格式吗？
• Do not underestimate the power of a well-crafted metaphor.不要低估精心构思的隐喻的力量。
• The haiku captures the beauty of nature in just seventeen syllables.俳句仅用十七个音节捕捉了自然之美。