1. しちかっけい   parallelogram   perpendicular lines   ellipse   heptagon   Hint Half-n-half Clue   2. へいこうしへんけい   segment   concave   parallel lines   parallelogram   Half-n-half Clue   3. らんけい   convex   oval   parallel lines   ellipse   Half-n-half Clue   4. たかっけい   rhombus   parallel lines   polygon   vertex   Half-n-half Clue   5. とうちょう   rhombus   vertex   parallel lines   pentagon   Half-n-half Clue   6. ごかっけい   oval   quadrangle   hemisphere   pentagon   Half-n-half Clue   7. しかっけい   parallelogram   quadrangle   edge   straight line   Half-n-half Clue