A story of Edison's boyhood will be told by our teacher.
原句的意思：一个关于爱迪生少年时代的故事将被我们老师讲.
改为主动语态则为：我们老师将要讲一个关于爱迪生少年时代的故事.
翻译成英文则为：Our teacher will tell us a story of Edison's boyhood.