Valmiki Ramayana Sundara Kanda Sarga 1 Shloka 132
Original Shlokaत्वरते कार्यकालो मे अहश्चाप्यतिवर्तते। प्रतिज्ञा च मया दत्ता न स्थातव्यमिहान्तरे।।5.1.132।।
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मे to me, कार्यकालः schedule, त्वरते hastens, अहः च the day also, अतिवर्तते exceeds, मया by me, प्रतिज्ञा vow, दत्ता च is made, अन्तरे in between, इह here, न स्थातव्यम् I will not halt.
"My commitment is hastening me. The day set (for the accomplishment of the task) is also drawing to a close. A vow is made and I will not halt in the middle of my work."