Valmiki Ramayana Kishkindha Kanda Sarga 29 Shloka 29
Original Shlokaतस्य तद्वचनं श्रुत्वा काले साधु निवेदनम्। सुग्रीवस्सत्त्वसम्पन्नश्चकार मतिमुत्तमाम्4.29.29।।
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तस्य his, काले at proper time, साधु honest, निवेदनम् advice, तत् वचनम् those words, श्रुत्वा on hearing, सत्त्वसम्पन्नः one who has great sense of duty, सुग्रीवः Sugriva, उत्तमाम् best, मतिम् mind, चकार set on.
Sugriva who had a great sense of duty, started applying his mind, when he heard the honest advice of Hanuman.