using {} for a and x for b, we get {x} for c. then use {x} for a and y for b, getting {x,y} for c. one may continue in this fashion to build up any finite set. blocks 

the area is divided into four blocks. . . and mountain pasture land of no value except for grazing purposes." its relative major is b-flat major and its parallel major is g major. crew 
the yacht's crew included fourteen men operating the ship. 