中文摘要：

朱翱重纽反切只能通过反切上字在一定程度上区别重纽。中古重纽可分为三种类型：《释文》型、慧琳《音义》型和朱翱反切型。《释文》型是通过切下字来区别重纽,代表以介音区别重纽的阶段;慧琳《音义》型则是切上字和切下字能够同时区别重纽,代表的是声母区别重纽的阶段;而朱翱反切型则只能通过切上字来区别重纽,且例外较多,代表的是以声母区别两类的重纽逐步走向混同的阶段。

英文摘要：

According to statistical analysis, we found that Chongniu（重纽） doublets was different from upper spellings, not lower spellings. We believe that they stand for three categories of Chongniu（重纽） in the middle ancient times. Type B（the third division Chongniu（重纽） final） is different from Type A（the fourth division Chongniu（重纽） final） in Chongniu（重纽） doublets ofdingdianshiwen（经典释文） because they have different head vowels. But Type B is different from Type A in Chongniu（重纽） doublets of Hui Lin（慧林） Yiqiejing yinyi（一切经音义） because they had different initials. Chongniu（重纽） in Zhu Ao（朱翱） Fanqie（反切） had the same characteristics as in Hui Lin（慧林） Yiqiejingyinyi（一切经音义）, but the difference of Chongniu（重纽） doublets had become not so clear.