Valmiki Ramayana Sundara Kanda Sarga 13 Shloka 10
Original Shlokaउपर्युपरि वा नूनं सागरं क्रमतस्तदा।।5.13.10।। विवेष्टमाना पतिता सागरे जनकात्मजा।
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तदा then, सागरम् उपर्युपरि higher and higher over the sea, क्रमतः for him while he advanced, जनकात्मजा Janaki, विवेष्टमाना wriggling hard to extricate, सागरे in the sea, नूनम् surely, पतिता fallen.
"Surely, she might have fallen into the sea while wriggling in her effort to extricate herself from the hold of Ravana as he was flying over the sea.