It is the nature of the mind to roam about.

心猿意马、头脑的习性是四处游荡.

He likes to roam about the city.

他喜欢在城市里流浪。

He is homeless and has to roam about.

他无家可归，只能四处流浪。

We roam about the countryside, enjoying the scenery.

我们在乡村流浪，享受自然风光。

I have done unnumbered wrongs, and aimlessly I roam about.

我犯了数不清的错误，也漫无目的地漫游着。