Valmiki Ramayana Ayodhya Kanda Sarga 33 Shloka 6
Original Shlokaयं यान्तमनुयाति स्म चतुरङ्गबलं महत्। तमेकं सीतया सार्धमनुयाति स्म लक्ष्मणः।।2.33.6।।
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यान्तम् while going, यम् whom, महत् powerful, चतुरङ्गबलम् army of four divisions, अनुयाति स्म used to follow, तम् such, एकम् alone, सीतया सार्धम् along with Sita, लक्ष्मणः Lakshmana, अनुयाति स्म followed.
Whenever Rama went out, powerful army of four divisions used to follow him. Today he is walking alone followed by Lakshmana and Sita.