How to use "disappearing" in a sentence

But now, with no sign of a rescue, my hopes are disappearing fast.

Marius ran to the gate and was just in time to see the figure of Eponine, Thenardier's daughter, disappearing into the shadows at the end of the street.

But she was so good at just melting away, disappearing before Sala had time to realize she was going

I saw the houses stretching away and disappearing into the smoke and mist, people walking up and down between the flower-beds, and the sightseers around the Martian machine that still stands there