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Dear Paul,

 I've just received / I've just been receiving your message to us all about the seminar on Friday. - Chọn -I've workedI've been working on my presentation for the last week, and - Chọn -have now finishednow finished it, so I am happy to be one of the first to present it, However, - Chọn -I've made I made an appointment to see the university careers advisor immediately after the seminar, so I will need to leave on time.

I'd like some advice about my presentation. At last week's lecture - Chọn -you've said you said that we should use visual aids as much as possible. - Chọn -I haven't found I didn't find anything to use. Is it essential? - Chọn -I've done I did lots of presentations before, and I feel OK about this one. In my last presentation - Chọn -I used I have been using the overhead projector, and I want to do this again - does this count as a visual aid?

One last question: - Chọn -I've been I went to Professor Russell's lecture yesterday, and - Chọn -have been learning learnt quite a lot that is relevant to this course. Is it okay to refer to another course in my presentation? - Chọn -I've been wondering I wondered about this - maybe it is better to stick to the materials and references - Chọn -you've given you've been giving us. I hope you can let me know.

Thanks for your help.

Sunita