a special kind of crossword called a word square

w

Language Log: Wordplay Watch #2: The hunt for the ten-square  http://itre.cis.upenn.edu/~myl/languagelog/archives/002679.html

【推广】 免费学中医，健康全家人
原文地址：https://www.cnblogs.com/rsapaper/p/6839138.html