Valmiki Ramayana Yuddha Kanda Sarga 102 Shloka 3
Original Shlokaएषरावणवीर्येणलक्ष्मणःपतितोभुविः । सर्पवच्चेष्टतेवीरोभूमौशोकमुदिरीयन् ।।6.102.3।।
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रावणवीर्येण prowess of Ravana, भुवि earth, पतितः fallen, एषः like that, वीरः hero, लक्ष्मणः Lakshmana, शोकम् sorrow, उदीरयन् writhing, सर्पवत् like snake, भूमौ on the ground, चेष्टते rolling
'Heroic Lakshmana struck by Ravana, fell on the ground and writhing like a snake and rolling made me sad'.