Valmiki Ramayana Yuddha Kanda Sarga 76 Shloka 75
Original Shlokaवरदानापतितृव्यस्तेसहतेदेवदानवान् । कुम्भकर्णस्तुवीर्येणसहते च सुरासुरान् ।।6.76.75।।
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ते your, पितृव्यः uncle, वरदानात् by the boons, देवदानवान् Devas and Danavas, सहते with stand, कुम्भकर्णस्तु Kumbhakarna also, वीर्येण courage, सुरासुरान् gods and demons, सहते with stand.
"Your uncle Ravana is able to withstand the Devas and Danavas by virtue of the boons and Kumbhakarna was able to with stand gods and demons by virtue of his courage."