独自一人

I was alone with no money or possessions.

我独，有钱，有财产。

He went to the bandits' lair all by himself!

他独闯了土匪窝。

I work more efficiently on my own.

我独工作效率更高。

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

虽然独生活少会有乐趣，但还是可以习惯的。

He was alone in the house.

他独在家里。

He was alone in the room.

他独在屋里。

He was unhappy when alone.

他独时感到不快活。