Valmiki Ramayana Aranya Kanda Sarga 44 Shloka 17
Original Shlokaम्रियमाणस्तु मारीचो जहौ तां कृत्रिमां तनुम्।।3.44.17।। स्मृत्वा तद्वचनं रक्षो दध्यौ केन तु लक्ष्मणम्। इह प्रस्थापयेत्सीता शून्ये तां रावणो हरेत्।।3.44.18।।
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मारीचः Maricha, म्रियमाणः breathing his last, कृत्रिमाम् artificial, ताम् that, तनुम् body, जहौ gave up, रक्षः the demon, तद्वचनम् those words, स्मृत्वा remembering, दध्यौ thought, सीता Sita, केन by what means, लक्ष्मणम् Lakshmana, इह here, प्रस्थापयेत् she may send, शून्ये in seclusion, ताम् her, रावणः Ravana, हरेत् will abduct.
Maricha gave up his false form of the deer and before breathing his last, remembered the words of Ravana. He thought over the means through which Sita could send Lakshmana to this spot so that Ravana would abduct her when she is alone.