Valmiki Ramayana Sundara Kanda Sarga 37 Shloka 34
Original Shlokaस तस्मात्पादपाद्धीमानाप्लुत्य प्लवगर्षभः। ततो वर्धितुमारेभे सीताप्रत्ययकारणात्।।5.37.34।।
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धीमान् wise, प्लवगर्षभः bull among monkeys, सः he, तस्मात् पादपात् from the tree, अप्लुत्य jumping down, ततः from there, सीताप्रत्ययकारणात् in order to instil confidence in Sita, वर्धितुम् to grow in size, आरेभे started.
The wise bull among monkeys, jumped down from the tree and started growing in size in order to instil confidence in Sita.