Valmiki Ramayana Ayodhya Kanda Sarga 20 Shloka 31
Original Shlokaस षट्चाष्टौ च वर्षाणि वत्स्यामि विजने वने। आसेवमानो वन्यानि फलमूलैश्च वर्तयन्।।2.20.31।।
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सः that (I am), वन्यानि forest products, आसेवमानः eating, फलमूलैः fruits and roots, वर्तयन् while living, षट्चाष्टौ च six and eight (fourteen), वर्षाणि years, विजने वने in the desolate forest, वत्स्यामि shall dwell.
Living on things available in the forest, on fruits and roots, I am to dwell in the uninhabited jungle for fourteen years.