Valmiki Ramayana Ayodhya Kanda Sarga 28 Shloka 3
Original Shlokaसीते महाकुलीनाऽसि धर्मे च निरता सदा। इहाऽचर स्वधर्मं त्वं मे यथा मनसस्सुखम्।।2.28.3।।
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सीते O Sita, महाकुलीना born in a noble race, सदा always, धर्मे to duty ,निरता असि you are devoted, इह here, यथा as, मे मनसः to my mind, सुखम् brings happiness, त्वम् you, स्वधर्मम् your duty, आचर practise.
Born in a noble race, O Sita, you are always devoted to duty. Follow your duty, here. It will make me happy.