ASCII to PDF

If he's planning to apply the corrections in Acrobat, this is a very bad idea.
Acrobat is not a word processor, although it is suitable for making comments. If he is planning to take your commented PDF and use that to edit his original file (which I assume is a plain text or Word file. ASCII is not a type of file but a basic type of character encoding), then that's fine, but don't expect to be able to apply the changes in Acrobat like you can do in Word.

Thanks, Try67, for responding. I apologize for being 'illiterate' about these things. I believe he wants me to make my corrections in PDF form in 'red' and then somehow convert it back to ASCII (or .txt) and attach it in an e-mail and send it back to him. Can I make corrections (changes) in PDF using Acrobat Reader in 'red' where he can see the words in 'red' as well? Hope I'm making myself clear. You have already been helpful and I appreciate it; hope you can help me further. I'm assuming that wherever he sees something in 'red' he knows that's a change he should make. Granny

It's impossible to change any of the text in a PDF using Reader. You need the Standard or Pro version for that, and even there you will find it extremely uncomfortable to make changes to the running text of a PDF file (in any color) of anything more than a single word at a time. Also, you can't have any colors in a txt file, since by definition it can only contain pure text.
Do it in Word, it has a built-in function (Track Changes) that was created especially for that.

Hey, Try67, Thank you, again, so much. You have been so helpful in helping a novice like me. Granny