霧がとても濃かったので、一寸先も見えなかった。

tbd

The mist was so dense that I could not see even an inch ahead.

彼あんなに元気だったのに。突然亡くなるなんて。一寸先は闇だね。

tbd

He was so healthy up to the minute of his sudden death. You really never know what might happen next.

一寸先は闇。

tbd

No one knows what the future holds.

Who can read the future?

Nobody knows what the future holds.