Valmiki Ramayana Ayodhya Kanda Sarga 52 Shloka 16
Original Shlokaनातिक्रान्तमिदं लोके पुरुषेणेह केनचित्। तव सभ्रातृभार्यस्य वासः प्राकृतवद्वने।।2.52.16।।
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सभ्रातृभार्यस्य of one with brother and wife, तव your, प्राकृतवत् like a common man, वने in the forest, वासः residing, इदम् this, इह लोके in this world, केनचित् पुरुषेण by any person, नातिक्रान्तम् not overcome.
None else in this world would be able to live in the forest as you have resolved to, like a common man, along with your brother and spouse.