Valmiki Ramayana Sundara Kanda Sarga 34 Shloka 10
Original Shlokaअहो धिग्दुष्कृतमिदं कथितं हि यदस्य मे। रूपान्तरमुपागम्य स एवायं हि रावणः।।5.34.10।।
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अहो Oh, धिक् fie upon, मे to myself, इदम् this, अस्य to him, कथितम् story, दुष्कृतम् that which should not have been said, अयम् he, रूपान्तरम् in cognito, उपागम्य has come, सः रावणः हि verily he is Ravana.
"Ohshame on me. I have told him my story which should not have been said. This is verily Ravana come in a disguise".