Appositive noun clauses were found to occur only 24 times in the 60 pages selected from 30 textbooks and 60 pages from 30 Yahoo News reports.

• 经观察三十本教科书中选出之六十页，及雅虎网站下载之三十篇新闻报导，研究者发现同位子句在这些文章中仅出现了二十四次。