A Chinese Ph.D. candidate was going to have a presentation. To better demonstrate his talk, he needed to cut an apple during the presentation, but he did not have a knife. So just before the presentation started, he went to his professor's office and asked, “May I borrow your life?” Immediately the professor's face turned perceivably red and jumped up from his chair starring at him perplexedly. It took a while for the student to realize something somehow not right. The student pointed to the knife on the table, “Oh, sorry, I meant, may I borrow your KNIFE to cut the apple?”