It is interesting to note that, since most of the Earth's exposed rock is of sedimentary origin and since sedimentary rocks are a by-product of weathering, most of the rocks that are weathering away in today's world are second or perhaps even third generation rocks.
(the rocks; are weathering away; ) (most of the Earth's exposed rock; is; of sedimentary origin) (sedimentary rocks; are; a by-product of weathering)
the rocks most of the Earth's exposed rock sedimentary rocks
are weathering away is are
of sedimentary origin
a by-product of weathering