上课铃响了，某中学高二的教室里，一位教师走上讲台，一声不吭地拿起粉笔在黑板上画了一个“○”，然后向全班学生提问：“请同学们回答这是什么？”时间一分一秒地过去了，同学们面面相视，都不敢冒然回答，后来班长站起来才打破了尴尬与沉闷，怯生生地说：“这可能是个零。 The class bell rang. In the middle school classroom of a high school, a teacher walked up to the podium, picked up the chalk without a word, drew a “○” on the blackboard, and then asked the whole class: “Please ask the students to answer this question. What?” The time passed in minute by minute. The students looked at each other and dared not respond rashly. The squad leader then stood up and broke the embarrassment and dreary. He said timidly: “This may be a zero.