1. へいめん   ellipse   hexagon   straight line   plane   Hint Half-n-half Clue   2. らんけい   oval   convex   ray   hexagon   Half-n-half Clue   3. へいこうせん   polygon   parallel lines   ellipse   parallelogram   Half-n-half Clue   4. とつめん   rhombus   convex   plane   parallel lines   Half-n-half Clue   5. ふち、はし   edge   pentagon   plane   parallel lines   Half-n-half Clue   6. へいこうしへんけい   heptagon   vertex   parallelogram   ray   Half-n-half Clue   7. りょうけい、はすほうけい   rhombus   vertex   hexagon   oval   Half-n-half Clue