Valmiki Ramayana Kishkindha Kanda Sarga 59 Shloka 23
Original Shlokaयत्तु शक्यं मया कर्तुं वाग्बुद्धिगुणवर्तिना।।4.59.23।। श्रूयतां तत्प्रवक्ष्यामि भवतां पौरुषाश्रयम्।
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वाग्बुद्धिगुणवर्तिना endowed with the faculty of thinking and speaking, मया by me, यत् such, कर्तुम् to execute, शक्यम् capable, भवताम् to you, पौरुषाश्रयम् with your prowess, तत्र there, वक्ष्यामि I shall tell, श्रूयताम् you may listen.
'Being endowed with the faculty of thinking and speech I shall tell you what is possible for you to execute with your prowess. Listen.