Valmiki Ramayana Kishkindha Kanda Sarga 29 Shloka 19
Original Shlokaतस्य त्वं कुरु वै कार्यं पूर्वं तेन कृतं तव। हरीश्वर कपिश्रेष्ठानाज्ञापयितुमर्हसि4.29.19।।
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हरीश्वर O king of monkeys, पूर्वम् earlier, तेन by him, तव to you, कृतम् done, त्वम् you, तस्य his, कार्यम् task, कुरु वै you may do, कपिश्रेष्ठान् आज्ञापयितुम् to order the best of monkeys, अर्हसि it will be proper for you.
'O king pray accomplish his object the same way he has accomplished your own. You ought to issue orders to the foremost of the monkeys.