The volcano crumbled into the sea.

The building crumbled to pieces three years ago.

Tom crumbled up biscuits and mixed them into the quark.

Phew! It hurts me to see my identity crumble.

Sami crumbled to the floor.

The old brickwork began to crumble.

Damn!  It hurts to see my identity crumble.

Everything crumbles as soon as I touch it.

The church we went past crumbled five minutes later due to a huge earthquake, and more than a hundred churchgoers were buried alive.

I crumbled one.