问题描述：
then的用法
Before Dr.Luther L.Terry,then the Surgeon General of the United States,issued his office’s first "Report on Smoking and Health" more than 30 years ago,thousands of articles had already been written on the effects of tobacco use on the human body.
请问上句中then是什么用法,我看不懂,觉得好像多余了
Before Dr.Luther L.Terry,then the Surgeon General of the United States,issued his office’s first "Report on Smoking and Health" more than 30 years ago,thousands of articles had already been written on the effects of tobacco use on the human body.
请问上句中then是什么用法,我看不懂,觉得好像多余了
问题解答：
我来补答展开全文阅读