Valmiki Ramayana Ayodhya Kanda Sarga 29 Shloka 12
Original Shlokaवनवासेऽभिजानामि दुःखानि बहुथा किल। प्राप्यन्ते नियतं वीर पुरुषैरकृतात्मभिः।।2.29.12।।
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वीर O valiant one, वनवासे while residing in the forest, दुःखानि hardships, बहुथा किल certainly of every kind, अभिजानामि I am aware, अकृतात्मभिः by those whose senses are not under their control, पुरुषैः by men, नियतम् definitely, प्राप्यन्ते will be experienced.
I am aware, O valiant one, that there are hardships of every kind in forest life. But they befall those whose senses are not under their control.