Valmiki Ramayana Ayodhya Kanda Sarga 52 Shloka 57
Original Shlokaचतुर्दश हि वर्षाणि सहितस्य त्वया वने। क्षणभूतानि यास्यन्ति शतसङ्ख्यान्यतोऽन्यथा।।2.52.57।।
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वने in the forest, त्वया with you, सहितस्य accompanied, चतुर्दश वर्षाणि fourteen years, क्षणभूतानि like a moment, यास्यन्ति will pass, अत: more than this, अन्यथा in any other way, शतसङ्ख्यानि (will seem like) a hundred years.
If I accompany you into the forest, fourteen years will pass like a moment, otherwise it will seem like a hundred years.