20 Ji sui yi ding yao dong dian jing ji xue

Ben shu yi jing ji xue de yuan li,Tan tao wo men shen bian xing xing se se,Yu sheng huo xi xi xiang guan de wen ti,Jiao hui nian qing ren yong jing ji xue de yan guang kan dai sheng huo he gong zuo,Bing zai bu tong de huan jing xia qiao miao di ying yong jing ji xue yuan li.