Valmiki Ramayana Kishkindha Kanda Sarga 1 Shloka 31
Original Shlokaअयं हि दयितस्तस्याः कालो रुचिरकाननः। कोकिलाकुलसीमान्तो दयिताया ममानघ।।4.1.31।।
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अनघ O Sinless one, मम to me, दयितायाः to my beloved wife, तस्याः of her, रुचिरकाननः beautiful forest, कोकिलाकुलसीमान्तः cockoos crowding the skirts, अयम् this, कालः (Spring) time, दयितः dear
'O sinless one, the spring season is dear to my beloved Sita when the outskirts of the forest are filled with voices of the cockoo.