1. segment   concavo   emisfero   quadrilateral   segmento   Hint Half-n-half Clue   2. convex   losanga   quadrangolo   konvex   concavo   Half-n-half Clue   3. edge   parallelogramma   bordo   concavo   poligono   Half-n-half Clue   4. parallel lines   ellisse   piano   linee parallele   linee perpendicolari   Half-n-half Clue   5. perpendicular lines   quadrilateral   linee perpendicolari   parallelogramma   prisma   Half-n-half Clue   6. plane   linee perpendicolari   piano   vertice   emisfero   Half-n-half Clue   7. polygon   poligono   raggio   konvex   bordo   Half-n-half Clue