The nation looked on and failed to notice the difference.

How could I have failed to notice all these years?

How could she have failed to notice anyone following her for so long?

What he failed to notice was that they were not alone.

And how had she failed to notice it for so long?

And when finally something did happen they failed to notice it.

But then, it seems I failed to notice a lot of things.

Was this something I had simply failed to notice before?

Had he simply failed to notice the signs of age on her?

He was pretty sure that no one could fail to notice.