Valmiki Ramayana Yuddha Kanda Sarga 41 Shloka 93
Original Shlokaरावणस्तुपरंचक्रेक्रोधंप्रासादधर्षणात् । विनाशंचात्मनःपश्यन्निश्श्वासपरमोऽभवत् ।।6.41.93।।
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रावणस्तु even Ravana, प्रासादधर्षणात् for shattering the palace, परम् very, क्रोधम् angry, चक्रे exhibiting, आत्मनः for him, विनाशम् destruction, पश्यन् seeing, निःश्वासपरमः sighing, अभवत् exhibited.
Ravana exhibiting extreme anger at the shattering of his palace and seeing his destruction started sighing heavily.