英语笑话带翻译一分钟 开心一笑:英语笑话:区别

开心一笑:英语笑话:区别  

"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 undergraduates respond
'Good afternoon." But the graduate students just write it down."