7.Thirteen new compounds of the alkyl styryl indoline spirobenzopyrans were synthesized from the condensation of 2-methylene indoline with the designed salicylaldehyde.
8.Approximately thirteen seconds before impact, the Copperhead's laser light sensor becomes active, and it uses fins to guide itself to the laser light source.
9.In chapter thirteen, Aristotle outlines an ideal of the central character of tragedy, the so-called tragic hero, and identifies the source of the character's downfall with something called hamartia.
何偶数除尽。
（汇总） 
的数字。
2-亚甲基吲哚啉和取代水杨醛缩合得到
尾翅制导攻击激光照射目标。
艰。
日综合录
和
三千？
