This is a particular landscape feature at a point in time.
This is the same feature after 1000 years of wind erosion.
This is the same feature after 10,000 years of wind erosion.
This is the same feature after 2 million years of wind erosion.
Look at each of the labels.
Look at the top picture. Can you decide under which label the picture should go?
Drag each of the pictures and drop them below the label to which you think they belong.
A YELLOW border will appear around those which are under the correct label.