0 to the place where someone or something was before -- 元に(へ), (元の位置に)戻って
When do you go back to college?
I put it back in the cupboard.
2 in a direction behind you -- 後ろへ(に), 後方へ(に)
She stepped back.
3 to the state something or someone was in before -- (元の状態に)戻って
Try to go back to sleep.
We can complete it step by step however long the road is and it can't be completed however short the road is if you don't even mark your footprint.
道路がどれだけ長くても、一歩一歩完了することができますし、足跡をマークしなければ、道路がどんなに短くても完了することはできません。