英语幽默:谁干的

One day after school the teacher said to his students, "Tomorrow morning, if any one of you can answer my first question, I will permit him or her to go home earlier."
一天，放学以后，老师对他的学生们说：“明天上午，如果你们当中的任何一个同学能首先回答我的问题，我就准许他或她最先回家。”
The next day, when the teacher came into the classroom, he found the blackboard daubed. He was very angry and asked, "Who did it? Please stand up!"
第二天，老师走进教室时发现黑板被涂得乱七八糟，他非常生气的问：“谁涂的？站起来！”
"It's me," said Bob, "Now, I can go home. Good-bye, Sir."
鲍勃说：“先生，是我，现在我可以回家了，再见！”