Valmiki Ramayana Ayodhya Kanda Sarga 11 Shloka 3
Original Shlokaप्रतिज्ञां प्रतिजानीष्व यदि त्वं कर्तुमिच्छसि। अथ तद्व्याहरिष्यामि यदभिप्रार्थितं मया।।2.11.3।।
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त्वम् you, कर्तुम् to accomplish, इच्छसि यदि if you are inclined, प्रतिज्ञां प्रतिजानीष्व promise to fulfil, अथ thereafter, मया by me, यत् whatever, अभिप्रार्थितम् sought for, तत् that one, व्याहरिष्यामि I will tell you.
If you are inclined to accomplish my desire, then promise me that you will fulfil them. Thereafter I shall reveal it to you.