1. parallélogramme   vertex   parallelogram   convex   hemisphere   Hint Half-n-half Clue   2. concave   parallelogram   parallel lines   oval   concave   Half-n-half Clue   3. ellipse   rhombus   ellipse   pyramid   plane   Half-n-half Clue   4. hexagone   convex   vertex   hexagon   perpendicular lines   Half-n-half Clue   5. pentagone   polygon   hexagon   pentagon   parallelogram   Half-n-half Clue   6. pyramide   ellipse   pyramid   heptagon   straight line   Half-n-half Clue   7. sommet   segment   concave   vertex   pyramid   Half-n-half Clue