1. pyramid   jin zi [da;ta]   fei ji   tu mian   si fang xing   Hint Half-n-half Clue   2. concave   [ao;wa] mian   ping [hang;hang;heng;xing] [de;di;di] xian   [leng;leng;ling] jing   duan   Half-n-half Clue   3. heptagon   qi [bian;bian] xing   wu [bian;bian] xing   [liu;lu] [jia;jiao;jue] xing   si [bian;bian] xing   Half-n-half Clue   4. rhombus   wu [bian;bian] xing   ling xing   fei ji   chui zhi xian   Half-n-half Clue   5. perpendicular lines   jin zi [da;ta]   tu mian   ban qiu   chui zhi xian   Half-n-half Clue   6. edge   jin zi [da;ta]   fei ji   duan dian   [bian;bian] yuan   Half-n-half Clue   7. polygon   duo [jia;jiao;jue] xing   tu mian   duan dian   wu [bian;bian] xing   Half-n-half Clue