By the side of a vessel sunk， a thousand sails are floating past. ; A thousand sailspass by the shipwreck. ; in front of a tree， sick with age, thousands of trees grow thick and fast ; in a face of a decaying tree, thousands of trees burst with life. ; It is in the nature of human society that new forces are always at work, not only to take the place of the old, the decadent, the moribund but also to thrive in abundance. ; Thousands of boats pass by the side of the sunken ship. ; Ten thousand saplings shoot up beyond the withered tree.