Valmiki Ramayana Yuddha Kanda Sarga 36 Shloka 14
Original Shlokaएवंब्रुवाणंसंरब्धंरुष्टंविज्ञायरावणम् । व्रीळितोमाल्यवान्वाक्यंनोत्तरंप्रत्यपद्यत ।।6.36.14।।
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एवं in that way, संरब्धम् abashed, ब्रुवाणम् speaking, रावणम् to Ravana, रुष्टम् anger, विज्ञाय knowing, माल्यवान् Malyavan, व्रीळितः feeling shy, उत्तरम् reply, वाक्यम् words, नप्रत्यपद्यत not uttered.
When Ravana was abashed and speaking in that way realizing that he is angry, Malyavan did not reply feeling shy.