○Unlike building materials, the methods of support used in architecture have not changed over time because they are based on physical laws.
Hills and mountains are often regarded as the epitome of permanence, successfully resisting the destructive forces of nature, but in fact they tend to be relatively short-lived in geological terms.
○When they are relatively young, hills and mountains successfully resist the destructive forces of nature.
○Although they seem permanent, hills and mountains exist for a relatively short period of geological time.
○Hills and mountains successfully resist the destructive forces of nature, but only for a short time.
○Hills and mountains resist the destructive forces of nature better than other types of landforms.