Valmiki Ramayana Sundara Kanda Sarga 51 Shloka 32
Original Shlokaरामेण हि प्रतिज्ञातं हर्यृक्षगणसन्निधौ।।5.51.32।। उत्सादनममित्राणां सीता यैस्तु प्रधर्षिता।
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रामेण by Rama, हर्यृक्षगणसन्निधौ in the presence of bears and vanaras, यैः by those, सीता Sita, प्रधर्षिता is troubled, अमित्राणाम् of enemy troops, उत्सादनम् exterminate, प्रतिज्ञातं हि indeed made a vow.
"Rama made a vow in the presence of bears and vanaras that he would exterminate the arrogant enemy troops by whom Sita is abducted and assaulted.