Valmiki Ramayana Yuddha Kanda Sarga 50 Shloka 21
Original Shlokaराज्यंप्राप्स्यसिधर्मज्ञ लङ्कायांनात्रसंशयः । रावणस्सहपुत्रेणस्वकामंनेहलप्स्यते ।।6.50.21।।
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धर्मज्ञ righteous, लङ्कायाम् in Lanka, राज्यम् kingdom, प्राप्स्यसि having got, अत्र and now, संशयः doubt, न no, रावणः Ravana, सहपुत्रेण with his sons, स्वकामम् of their desire, इह now, नलप्स्यते not attain.
"O righteous one! there is no doubt that you will attain the kingdom of Lanka. Ravana and his sons will not attain what they desire."