|
A Japanese student of ninja history who handed in a blank paper was given top marks - after her professor realised the essay was written in invisible ink. 日本一名研究忍者历史的学生论文交了“白卷”，却得到了最高分，因为教授发现这篇文章是用隐形墨水写的。 Eimi Haga followed the ninja technique of "aburidashi", spending hours soaking and crushing soybeans to make the ink. 羽贺英美采用了一种忍者“烤墨纸”技术，她花费数小时浸泡、研磨豆子来制作墨水。 The words appeared when her professor heated the paper over his gas stove. 教授把她的论文放到煤气炉上方加热后，论文就显示了出来。 | 
