Valmiki Ramayana Sundara Kanda Sarga 30 Shloka 19
Original Shlokaअवश्यमेव वक्तव्यं मानुषं वाक्यमर्थवत्।।5.30.19।। मया सान्त्वयितुं शक्या नान्यथेयमनिन्दिता।
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अवश्यमेव certainly, मया by myself, अर्थवत् for that reason, मानुषम् common man's, वाक्यम् language, वक्तव्यम् should speak, अनिन्दिता siness lady, इयम् this, अन्यथा otherwise, सान्त्वयितुम् to pacify her, शक्या possible.
"I will certainly speak to her meaningfully in the language of the people. Otherwise it is not possible to pacify the sinless Sita.