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　　　　　　　　　　　　　　　　　　　　　　　　 My Life at Renda I learned very quickly that being a teaching assistant(TA)at the University of Iowa would be different from being a teacher at Renmin University. (46) Eyes staring, mouths open, students examined my big nose, while was writing my name on the blackboard. At Iowa,when my first classes began,half of my students still hadn’t arrived. When veryone finally found a seat,ringing cell phones and loud yawns(哈欠)interrupted my opening remarks. It is not that American students were disrespectful. (47) They were, however, far more skeptical than the students I had at Renda. The truth is I Couldn’t fault them for their skepticism. Undergraduates at large US universities -- especially freshmen and sophomores -- often have several classes a semester handled by TAs. In some cases,the TA sets the course content. (48) Most have good