题目内容：
根据以下材料，回答题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 stating, mouths open, students examined my big nose, while I was writing my name on the blackboard.
At Iowa, when my first classes began, half of my students still hadn't arrived. When everyone finally found a seat, ringing cellphones 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 intentions, but very few are as effective as professors.
Every teacher has to confront obstacles to leaming -- no matter what the culture. Students who talk during lecture, students who cheat, students who question the grade they get for a paper or project-- dealing with these is all part of the job. 49_______
The difference, I think, is that in the US I had to swallow more of my pride. 50_______ I had a responsibility to teach them, of course, but I had to do so indirectly-- as a guide who himself had a few things to learn from the students.
回答(46)题 A．In my students' minds, I had little to offer them, except perhaps some sample questions for the mid-term exam.
B．In others, the TA works as a grader and discussion leader.
C．I encountered these in China, and I fared them in the US.
D．On the other hand, being taught by a graduate student is not necessarily bad.
E．Most were polite, or at least, indifferent.
F．Back at Renda, I had walked into my first classes feeling like a celebrity.
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