21.   The family settled in one of the slums that extend from Lima in ever-expanding concentric rings.

22.   The five concentric rings should be replaced by a line of zeroes broken only by commas.

23.   The one most likely to prevail is known as the concentric rings.

24.   The Pentagon building has five concentric rings and officials said the plane penetrated at least three of them.

25.   The sight of nearly a dozen newly pummeled villages, surrounded by concentric rings of tanks and wailing refugees, only reinforces that notion.

26.   The spots, which consist of concentric rings, can grow together, covering the leaf.

27.   Then you get concentric rings of new recruitment.

28.   Two concentric rings of trees would mark the inner and outer edges of the circle, which would be carpeted with granite cobblestones.

29.   You start by moving the litter box close to the toilet and then you can use a system of litter-filled concentric rings that fit into the toilet.

30.   The room, with its concentric rings of reference-book shelves, is shaped like a bicycle wheel, with a circular inquiry desk at the hub.