A poem is identifiable by its literary and musical elements. For example, metaphor and alliteration are common in many poems. Another hallmark of a poem is its brevity, or ability to say much in few words. This requires layered meaning, as in the use of symbolism. A common example of symbolism is the bald eagle, which is a bird, but in the United States also represents the nation as a whole. A poem need not rhyme or contain a consistent meter to qualify as such, but those elements are also common to many poems
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