[解析]
M:Hello,professor Keller,you wanted to see me?
W:Oh Yes,Tom,it's about your work as a teaching assistant.
M:Thanks to the job.I learn a lot these days.
W:I'm glad to hear that.
Students in your class think highly of your work abilities.
M:Well What a pleasant surprise?
W:So We hope you can cover more classes.
What do you say?Tom?
Would you like to handle a load in the fall?
M:I sure would,but I don't know if I can.
Next fall i'll be very busy doing research on my paper.
Could I have a few days to think about it?
W:Certainly.