Here is a road before an earthquake: straight, flat and whole.

Before: a straight road across flat ground.

The earthquake strikes. The ground shakes hard for about twenty seconds.

As it shakes, the ground cracks in places.

One crack runs across the road. The crack is about as wide as your hand.

One side of the crack ends up a step higher than the other.

After: a crack across the road, and the right side a step higher.

The shaking stops. The crack and the step stay.

Before and after: the earthquake took about twenty seconds, and the road changed.