About the sixth century A.D.when few Europeans could read,the Chinese had invented paper.

题目

About the sixth century A.D.when few Europeans could read,the Chinese had invented paper.
这句话后面是主句我知道,但是前面的关系我有点搞不懂 About the sixth century A.D.是时间状语?when few Europeans could read不是也是么 那两个时间状语直接连起来怎么那么别扭

答案

句子的意思是：大约公元6世纪,当少数欧洲人会识字的时候,中国人已经发明了纸张.
About the sixth century A.D.是介词短语作时间状语,表示的是比较具体的世纪,相当与一个时间点,而when 是连词,引导一个时间状语从句
两个状语之间可以加逗号About the sixth century A.D.,when few Europeans could read
也可以直接像原句