“到他十岁的时候 就已经学完了高等数学”用英语怎么说 填空_____ _____ _____ he was ten,he _____ _____ advanced math.
问题描述：
“到他十岁的时候 就已经学完了高等数学”用英语怎么说 填空
_____ _____ _____ he was ten,he _____ _____ advanced math.
答
By the time when he
答
应该是 By the time ;had finished
by the time引导的句子,主句要用过去完成时