Valmiki Ramayana Ayodhya Kanda Sarga 85 Shloka 14
Original Shlokaएवं सम्भाषमाणस्य गुहस्य भरतं तदा। बभौ नष्टप्रभस्सूर्यो रजनी चाभ्यवर्तत।।2.85.14।।
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तदा then, गुहस्य Guha's, एवं thus, भरतं to Bharata, सम्भाषमाणस्य while conversing, सूर्यः sun, नष्टप्रभः diminished light, बभौ shone, रजनी च night, अभ्यवर्तत set in.
As Guha was thus conversing with Bharata, the rays of the Sun diminished and the night set in.