1. perpendicular lines   linee perpendicolari   bordo   segmento   pentagono   Hint Half-n-half Clue   2. quadrilateral   vertice   quadrilateral   concavo   pentagono   Half-n-half Clue   3. segment   segmento   losanga   linee parallele   raggio   Half-n-half Clue   4. concave   emisfero   quadrilateral   raggio   concavo   Half-n-half Clue   5. vertex   losanga   bordo   ovale   vertice   Half-n-half Clue   6. polygon   segmento   vertice   konvex   poligono   Half-n-half Clue   7. convex   konvex   pentagono   esagono   ovale   Half-n-half Clue