Valmiki Ramayana Aranya Kanda Sarga 48 Shloka 1
Original Shlokaएवं बृवन्त्यां सीतायां संरब्दः परुषं वचः। ललाटे भृकुटीं कृत्वा रावणः प्रत्युवाच ह।।3.48.1।।
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सीतायाम् when Sita, एवम् in that way, बृवन्त्याम् as she spoke, रावणः Ravana, संरब्धः roused to anger, ललाटे forehead, भृकुटीम् knitted eyebrows, कृत्वा doing, परुषम् harsh, वचः words, प्रत्युवाच replied.
Addressed thus by Sita, Ravana, his anger roused, knitted his eyebrows with a frown on his forehead and replied to her harshly: Ravana takes on his true form -- speaks of his glory -- Sita abuses Ravana in harsh words.