Valmiki Ramayana Aranya Kanda Sarga 72 Shloka 19
Original Shlokaशक्तौह्यद्य युवां कर्तुं कार्यं तस्य चिकीर्षितम्।।3.72.19।। कृतार्थो वाऽकृतार्थो वा कृत्यं तव करिष्यति।
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युवाम् you both, अद्य now, तस्य his, चिकीर्षितम् desired, कार्यम् his work, कर्तुम् to do, शक्तौ हि you both have the ability, कृतार्थो वा whether his work is done, अकृतार्थो वा or not done, तव your, कृत्यम् work, करिष्यति he will do.
You are both young and able to do the work he wants. Whether his work is done or not, he will fulfil your task.