独自一人

One can habituate oneself to living alone, though rarely with any pleasure.

虽然一人生活很少有趣，但还是可以习惯的。

I work more efficiently on my own.

我一人工作效率更高。

He went to the bandits' lair all by himself!

一人闯了土匪。

I was alone with no money or possessions.

我一人，没有钱，也没有财产。

He was alone in the house.

一人在家里。

He was alone in the room.

一人在屋里。

He was unhappy when alone.

一人时感到不快活。