Valmiki Ramayana Ayodhya Kanda Sarga 62 Shloka 19
Original Shlokaतं हि चिन्तयमानाया श्शोकोऽयं हृदि वर्धते। नदीनामिव वेगेन समुद्रसलिलं महत्।।2.62.19।।
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तम् Rama, चिन्तयमानायाः while thinking of, हृदि in my heart, अयम् this, शोकः sadness, नदीनाम् by river waters, वेगेन by speed, महत् great, समुद्रसलिलमिव like seawaters, वर्धते is increasing.
As I think of Rama, my heart swells with sorrow just as the ocean rises with rushing rivers.