Valmiki Ramayana Yuddha Kanda Sarga 65 Shloka 23
Original Shlokaवानराहिमहात्मानश्शीघ्रास्सव्यवसायिनः ।।6.65.23।। एकाकिनंप्रमत्तंवानयेयुद्धशनैःक्ष्यम् ।
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महात्मानः gigantic, शीघ्रा: endowed with speed, सुव्यवसायिनः full of determination, वानराः Vanaras, एकाकिनम् alone, प्रमत्तंवा not alert, दशनैः with teeth, क्ष्यम् destroy.
"The Vanaras are gigantic, endowed with speed and determination. They will destroy with their teeth when you are not alert and alone."