Valmiki Ramayana Kishkindha Kanda Sarga 28 Shloka 31
Original Shlokaतटित्पताकाभिरलङ्कृताना मुदीर्णगम्भीरमहारवाणाम्। विभान्ति रूपाणि बलाहकानां रणोद्यतानामिव वानरणानाम्4.28.31।।
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तटित्पताकाभिः banners of lightning, अलङ्कृतानाम् of the decorated, उदीर्णगम्भीरमहारवाणाम् making loud sound, वलाहकानाम् of the thundering clouds, रूपाणि forms, रणोत्सुकानाम् ready to fight in battle, वानराणाम् इव like elephants in rut, विभान्ति shine.
'The rainclouds decorated with banners of lightning and giving out peals of thunder shine like elephants in rut trumpeting, eager to fight in battle.