Valmiki Ramayana Aranya Kanda Sarga 64 Shloka 32
Original Shlokaएवमुक्तस्तु रामेण पर्वतो मैथिलीं प्रति। शंसन्निव ततस्सीतां नादर्शयत राघवे।।3.64.32।।
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रामेण by Rama, मैथिलीं Maithili, प्रति towards, एवम् in that way, उक्तः having said, पर्वतः mountain, ततः thereafter, सीताम् Sita, शंसन्निव appeared as if telling, राघवे to Rama, नादर्शयत not shown.
Thus addressed by Rama, the mountain echoed as if it was telling about Sita but did not show her to Rama.