Valmiki Ramayana Yuddha Kanda Sarga 63 Shloka 28
Original Shlokaतमथैवंब्रुवाणंतुवचनंधीरदारुणम् ।।6.63.28।। रुष्टोऽयमितिविज्ञायशनैश्श्लक्षणमुवाच ह ।
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अथ and then, एवम् in that way, धीरदारुणम् grave and harsh, वचनम् tone, ब्रुवाणम् arguing, तम् him, अयम् exceedingly, रुष्टः agitated, इति thus, विज्ञाय knowing, सः he, शनैः slowly, श्लक्षणम् gentle tone, उवाच ह spoke.
Thereafter knowing that Ravana is agitated and arguing in a grave and harsh manner, Kumbhakarna, spoke slowly in a gentle tone.