ReadingComp-Quiz-15 (Explanation)

Making a sandcastle is a favorite project of beach-goers of all ages. Begin by digging up a large amount of sand (enough to fill at least six pails) and arranging it in a pile. Then, scoop the sand into your pail, patting it down and leveling it off at the rim as you do. You can now construct the towers of your castle by placing one pailful of sand after another face down on the area of the beach that you have staked out for yourself. Make four towers, placing each mound twelve inches apart in a square. This done, you are ready to build the walls that connect the towers.

The primary focus of this passage is _______________.