fan trained tree是什么意思

用法例句

This paper makes an analysis of the two features of the dialect words in distribution in shuo wen jie zi by investigating the 158 dialect words in it:relative concentration and fan-shaped distribution revolving around Runan and the reason for such a distribution.

许慎《说文解字》中标明的 15 8个方言词语 ,其在区域上有两个明显特征 :一是相对集中 ,二是以汝南为中心扇状分布。