Valmiki Ramayana Aranya Kanda Sarga 51 Shloka 36
Original Shlokaस तथा गृध्रराजेन क्लिश्यमानो मुहुर्मुहुः।।3.51.36।। अमर्षस्फुरितोष्ठस्सन्प्राकम्पत च रावणः।
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गृध्रराजेन by the king of vultures, मुहुर्मुहुः again and again, तथा in that manner, क्लिश्यमानः being tormented, सः रावणः he, Ravana, अमर्षफुरितोष्ठः सन् with his lips quivering with anger, प्राकम्पत was shaken.
Thus tormented again and again by the king of vultures, Ravana shook with anger, his lips quivering.