什么叫推波倍投公式

简介：——The three rushing Mongolian armies gradually slowed down when they were still two or three miles away from the Great Wall, and finally stopped. Then, the Mongolian soldiers on horseback jumped off their horses, holding shields and swords in their hands, and began to line up. Then someone else took out simple ladders from the carriage that was following them, and lined up rows and teams, as if they were preparing to attack the city.