Valmiki Ramayana Yuddha Kanda Sarga 86 Shloka 4
Original Shlokaसत्वमिन्द्राशनिप्रख्यैःशरैरवकिरन्परान् । अभिद्रवाशुयावद्वैनैतत्कर्मसमाप्यते ।।6.86.4।।
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सः he, त्वम् by you, इन्द्राशनिप्रख्यैः like Indra's thunderbolt, शरैः arrows, परान् at enemy, अवकिरन् use, एतत् by that, कर्म action, यावत् all, न समाप्यते not completed, आशु quickly, अभिद्रववै not attack
"You have come to attack the enemy. Before he completes his action quickly attack him with the thunderbolt of Indra."