Valmiki Ramayana Kishkindha Kanda Sarga 58 Shloka 3
Original Shlokaवृद्धभावादपक्षत्वाच्छृण्वंस्तदपि मर्षये। न हि मे शक्तिरस्त्यद्य भ्रातुर्वैरविमोक्षणे।।4.58.3।।
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तत् that, श्रुण्वन् अपि even after hearing , वृद्धभावात् due to old age, अपक्षत्वात् since I have no wings, मे to me, अद्य now, भ्रातुः brother's, वैरविमोक्षणे to avenge the death, शक्तिः energy, नास्ति हि I do not have.
'Even after I have heard this, I cannot avenge my brother's death as I am old, I have no wings, and I have no energy enough (to fight).