〔R13〕  It has cities, but no houses;

                 It has forests, but no trees;

                 It has rivers, but no fish.

〔譯註〕 它有城市，但沒房子；

                  它有森林，但沒有樹；

                  它有河流，但沒有魚。

〔提問〕 If it is not a mop (抹布) but sounds somewhat like it, what is it?

〔謎底〕  m__