Questions

Hi,
I would say:

1. ok.
2. no. Why can't he go? or: Why can he not go?
3. ok
4. ok.
5. ok.

By the way, use a capital "I" instead of "i".

By the way the question : "why can he not go?" sounds kind of unusual and does it mean the same as "why can't he go?"

Well, actually, all of those sentences where "not" is not contracted are not the usual ones. I think native speakers usually say "Why can't I do...?" instead of "Why can I not do...?"
That doesn't mean they are wrong or odd, it's just that the forms that are not contracted are more emphatic.

I think the only case where you can't use a contraction in a question is when you have a ques

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would anyone please re-confirm that this is correct please

What are you looking for confirmation on?

Why can he not go? and Why can't he go? - same meaning, but the first is far less likely to be heard.

Anthonhi check my sentences here please 1. Why can i not do that next time? 2. Why he can't go? 3. What can i not do for him? 4 What can't i say about him? 5. Where can i not meet him? Thanks, please correct the wrong ones, once again thanks

Hi Anthon

"i" should always be capitalized.