Valmiki Ramayana Sundara Kanda Sarga 50 Shloka 11
Original Shlokaअनृतं वदतश्चापि दुर्लभं तव जीवितम्।।5.50.11।। अथवा यन्निमित्तस्ते प्रवेशो रावणालये।
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तव your, अनृतम् false, वदतः while you speak, जीवितम् life, दुर्लभम् difficult, अथवा or else, रावणालये in the abode of Ravana, ते प्रवेशः your entry, यन्निमित्तः for waht reason.
"If you tell a lie, it will be difficult for you to live. Or else, tell me for what reason have you entered the abode of Ravana.'