Complex sentence: The idol's composition of metals is interpreted as a series of four successive kingdoms, starting with Nebuchadnezzar; all of these dominions will be crushed by God's kingdom, a kingdom that will "endure forever".
Split into simpler sentences: The idol's composition of metals is interpreted as a series of successive kingdoms, starting with Nebuchadnezzar. Finally all of these dominions are crushed by God's kingdom, a kingdom that will "endure forever".