Valmiki Ramayana Yuddha Kanda Sarga 37 Shloka 6
Original Shlokaतथातेषुब्रुवाणेषुरावणावरजोऽब्रवीत् । वाक्यमग्राम्यपदवत्पुष्कलार्धंविभीषणः ।।6.37.6।।
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तथा like that, तेषु they, ब्रुवाणेषु speaking to one another, रावणावरजः Ravana's brother, विभीषणः Vibheeshana, अग्राम्यपदवत् courteous words, पुष्कलार्थम् meaningful, वाक्यम् words, अब्रवीत् spoke.
While they were speaking like that to one another, Ravana's brother Vibheeshana spoke courteously, words full of meaning.