Most people believe that the landscape is (1) , but Earth is a (2) body with a continually (3) surface. There are 2 principal influences that shape the (4) : constructive process such as (5) and (6) forces such as erosion.
Hills and mountains are often regarded as the (7) of permanence. But, interestingly enough, the higher a mountain is, the more (8) it was formed. Lower mountains tend to be (9) and are often the eroded (10) of much higher mountain chains.
The earth’s crust is thought to be divided into huge, (11) segments, called plates, which (12) on a soft plastic layer of rocks. Some mountains are formed as a result of these crustal plates (13) into each other, and forcing up the rock at the plate (14) . Some mountains may be raised by (15) or formed as a result of (16) activity.
Any landscape represents only a (17) stage in the continuous (18) between different forces. The main agent of erosion is (19) . The landscape is continually eroded by rain, ice, tree roots and (20) .