Valmiki Ramayana Ayodhya Kanda Sarga 66 Shloka 9
Original Shlokaविदेहराजस्य सुता तथा सीता तपस्विनी। दुःखस्यानुचिता दुःखं वने पर्युद्विजिष्यति।।2.66.9।।
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तथा also, तपस्विनी a miserable woman, दुःखस्य of hardships, अनुचिता unworthy, विदेहराजस्य king Videha's, सुता daughter, सीता Sita, वने in the forest, दुःखम् great sorrow, पर्युद्विजिष्यति will be agitated in her mind.
In the same way Sita, daughter of the king of Videha, who does not deserve hardships will be in deep agony.