Any moment these walls may crumble upon us if you say such things.

Behind them the wall between the second and third dimensions is crumbling.

So why does it seem that the administration's wall of discipline is crumbling?

Some had no floor tiles and their walls were crumbling.

The wall was crumbling and there were great gaps in it.

To a ghost city, whose walls have long since crumbled.

But the walls of her world, already so fragile, crumbled then and there.

The walls of the place were crumbling and had clearly been reconstructed several times.

The outer walls crumbled under the first impact of the sea.

Laura was certain the walls Crystal had put up were quickly crumbling.