Valmiki Ramayana Yuddha Kanda Sarga 58 Shloka 59
Original Shlokaनशेकुस्समवस्थातुंनिहतेवाहिनीपतौ । सेतुबन्धंसमासाद्यविशीर्णंसलिलंयथा ।।6.58.59।।
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वाहिनीपतौ CommanderinChief, निहते killed, विशीर्णम् breached, सेतुबन्दम् dam, समासाद्य reaching, सलिलंयथा like the water, समवस्थातुम् stationary, नशेकुः not remain.
The CommanderinChief having been killed the troops could not remain there just as water reached a breached dam.