1. quadrilatère   polygon   quadrangle   pyramid   pentagon   Hint Half-n-half Clue   2. lignes perpendiculaires   oval   heptagon   ray   perpendicular lines   Half-n-half Clue   3. plat   hexagon   ray   concave   plane   Half-n-half Clue   4. convexe   heptagon   convex   hexagon   parallelogram   Half-n-half Clue   5. polygone   polygon   parallel lines   vertex   straight line   Half-n-half Clue   6. sommet   vertex   pentagon   ray   parallelogram   Half-n-half Clue   7. quadrilatère   quadrilateral   plane   hemisphere   pentagon   Half-n-half Clue