Valmiki Ramayana Sundara Kanda Sarga 26 Shloka 25
Original Shlokaअन्विष्य रक्षसां लङ्कां कुर्याद्रामस्सलक्ष्मणः। न हि ताभ्यां रिपुर्दृष्टो मुहूर्तमपि जीवति।।5.26.25।।
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सलक्ष्मणः accompanied by Lakshmana, रामः Rama, रक्षसाम् of the demons, लङ्काम् Lanka, अन्विष्य after searching, कुर्यात् will do, ताभ्याम् by both of them, दृष्टः sight, रिपुः enemy, मुहूर्तमपि even for a moment, न जीवति हि will not be alive.
"If only Lakshmana and Rama in their quest for Lanka reach here, it is not possible within their sight for the enemy to survive even a moment.