Final answer:
The phrase 'narrow domestic walls' in the poem symbolizes societal divisions that hinder communication and unity, and the line 'broken up into fragments' supports this interpretation.
Step-by-step explanation:
In the context of the poem, the phrase narrow domestic walls tends to symbolize divisions among people, especially at the societal level. The term 'narrow' signifies limitation and constraints, whereas 'domestic walls' may suggest segregation based on domestic confines, perhaps hinting at social, cultural, or ideological boundaries that inhibit communication, understanding, and a sense of togetherness among people.
In answering part b of your question, the line that best supports the phrase 'narrow domestic walls' could be 'broken up into fragments'. This line further emphasizes the idea of division and separation among individuals or groups.
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