An earthquake is a sudden shaking or disturbance of the earth's surface caused by movements in the earth's outer layer.
(An earthquake; is; a sudden shaking or disturbance of the earth's surface caused by movements in the earth's outer layer) (a sudden shaking or disturbance of the earth's surface; caused; by movements in the earth's outer layer)
An earthquake a sudden shaking or disturbance of the earth's surface
is caused
a sudden shaking or disturbance of the earth's surface caused by movements in the earth's outer layer
by movements in the earth's outer layer