我想要一段英语的幽默笑话，说有

1. Virtue

Many years after receiving my graduate degree, I returned to the State University of New York at Binghamton as a faculty member. One day in a crowded elevator, someone remarked on its inefficiency. I said the elevators had not changed in the 20 years since I began there as a student.

When the door finally opened, I felt a compassionate pat on my back, and turned to see an elderly nun smiling at me. "You'll get that degree, dear," she whispered. "Perseverance is a virtue."
美 德

获取研究生学位多年以后，我回到位于宾翰顿的纽约州立大学当教员。一天，电梯里很拥挤，有人抱怨电梯效率太低。我说自我在那里当学生起，20年来电梯一直没有换过。

最后当电梯门打开时，我感到有人在我的背上同情地拍了一下，回过头来我看到一位年长的修女正在朝我微笑。“你会拿到学位的，亲爱的，”她低声说道：“坚持不懈是一种美德。”
2. Difference

"I can always tell a graduate class from an undergraduate class," observed the instructor in one of my graduate engineering courses at California State University in Los Angeles. "When I say, 'Good afternoon,' the