1. りょうけい、はすほうけい   vertex   concave   plane   rhombus   Hint Half-n-half Clue   2. とうちょう   perpendicular lines   oval   vertex   segment   Half-n-half Clue   3. すいせん   pentagon   vertex   perpendicular lines   plane   Half-n-half Clue   4. しちかっけい   segment   edge   vertex   heptagon   Half-n-half Clue   5. とつめん   ellipse   pentagon   hemisphere   convex   Half-n-half Clue   6. はんきゅうたい   hemisphere   heptagon   hexagon   perpendicular lines   Half-n-half Clue   7. こうせん   ray   hemisphere   edge   ellipse   Half-n-half Clue