1. Thanks very much for your invitation to speak at the conference.
This sentence is correct.
2. I am considering sevral ideas which I think you will find interesting.
The misspelled word is: sevral. Correct spelling: several
3. First though, coiuld you let me know how many minutes my presentation will be?
The misspelled word is: coiuld. Correct spelling: could
4. Also, will I be able to show slides or use the overhead projector to show some grafs ?
The misspelled word is: grafs. Correct spelling: graphs
5. The sales figures of my division are quiet interesting, and reveal promising growth.
The misspelled word is: quiet. Correct spelling: quite
6. This is despite the downturn in the economy in the second quater of the year.
The misspelled word is: quater. Correct spelling: quarter
7. Or pehaps you would prefer if I mentioned the division's future prospects?
The misspelled word is: pehaps. Correct spelling: perhaps
8. Give it your consideration, and let me know if there are any other themes I shuold mention.
The misspelled word is: shuold. Correct spelling: should
