1. retas paralelas   quadrilateral   parallel lines   parallelogram   polygon   Hint Half-n-half Clue   2. retas perpendiculares   plane   ray   perpendicular lines   parallel lines   Half-n-half Clue   3. quadrilátero   quadrilateral   hexagon   quadrangle   pyramid   Half-n-half Clue   4. raio   ray   pyramid   convex   straight line   Half-n-half Clue   5. côncavo   parallel lines   concave   hemisphere   ray   Half-n-half Clue   6. losango, rombo   oval   parallelogram   rhombus   plane   Half-n-half Clue   7. prisma   concave   perpendicular lines   ellipse   prism   Half-n-half Clue