1. heikousen   polygon   convex   parallel lines   hemisphere   Hint Half-n-half Clue   2. fuchi、hashi   edge   oval   perpendicular lines   rhombus   Half-n-half Clue   3. chokusen   convex   segment   quadrilateral   straight line   Half-n-half Clue   4. shikakkei   ellipse   quadrangle   pentagon   ray   Half-n-half Clue   5. kukiri,bubun   ray   segment   rhombus   parallel lines   Half-n-half Clue   6. totsumen   ellipse   hexagon   convex   parallelogram   Half-n-half Clue   7. chouen   rhombus   ellipse   hexagon   quadrangle   Half-n-half Clue