Illegible: Essay or Criticism?
　　　
After Professor Brown returned some corrected essays to the students, a puzzled student raised his hand. Pointing to a word the professor had circled in his essay, he said, "I can't read what you wrote about it in the margin, sir."
After intense scrutiny the professor finally deciphered his criticism: "Illegible."

难以辨认：论文还是评语？

布朗教授把批改过的作文发给学生后，一个迷惑不解的学生举手提问。他指着在他作文上用红笔圈的字说道，“我看不出关于这个字你在边页上写的是什么。”
经过仔细认真地研究，这位教授才辨认出他自己的评语：难以辨认。