要我翻译的话这句话的意思应该是：这是他在信里的承诺.主语是in his letter . 但是我个人认为这句话这样说比较好：his promise was in his letter .这样的话主语是his promise .也不知道说得对不对,希望对你有用. 再问： 有点道理啊，但是说不清道不明的理由和用法 再答： 主语是in his letter 呀，这不只是一个单纯的句子吧，你最好能把它所在的那段句都写出来，那样可能会更好判断一些。 再问： 原句是一个同位语从句： In his letter was his promise that he would spend the Christmas Eve with me. 我现在也觉得是有点倒装的意思
