"A friend lies down on the road."
Translation:친구가 길에 누워요.
I spoke with my partner who is a native korean speaker and she clarified that sleep is actually considered actionable and therefore is used with 에서. However the premise of this is correct. E.g. laying, sitting, standing in a certain place = 에, while actions like jumping, running, sleeping = 에서. If you were to see some one laying down, getting up, laying back down repeatedly, you could then use 에서 because it has become actionable.