1. hexagone   convex   plane   hexagon   segment   Hint Half-n-half Clue   2. polygone   parallel lines   parallelogram   polygon   hexagon   Half-n-half Clue   3. ellipse   parallel lines   ellipse   pentagon   plane   Half-n-half Clue   4. lignes parallèles   segment   plane   convex   parallel lines   Half-n-half Clue   5. parallélogramme   parallelogram   segment   concave   prism   Half-n-half Clue   6. pentagone   ellipse   hexagon   pentagon   concave   Half-n-half Clue   7. segment   ray   segment   quadrangle   hexagon   Half-n-half Clue