Valmiki Ramayana Ayodhya Kanda Sarga 24 Shloka 17
Original Shlokaइमानि तु महारण्ये विहृत्य नव पञ्च च। वर्षाणि परमप्रीतः स्थास्यामि वचने तव।।2.24.17।।
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इमानि these, नव पञ्च च nine plus five (fourteen), वर्षाणि years, महारण्ये in the wild forest, विहृत्य having roamed, परमप्रीतः with supreme pleasure, तव your, वचने words (obeying your word), स्थास्यामि shall abide by.
Roaming the wild forest for fourteen years I shall abide by your words with supreme pleasure.