Thank you for this valuable information.

Isn’t “have” either an auxiliary verb or verb and “of” a preposition?

Are these acceptable? If yes, why? If not, why not?

• I of heard that story before.

• Diane of already gone.

• John ofn’t phoned, of he?

• I ofn’t visited London before.

• Of you seen Roz?

• Of she been invited?

• They still ofn’t of any news when I spoke to them yesterday.

I don’t know man, Oxford Dictionary (click Grammar Point to expand) says that https://www.oxfordlearnersdictionaries.com/definition/english/have_2

A common mistake is to write ‘could of’ instead of could have or could’ve

I could of told you that.

I could’ve told you that.

The reason for the mistake is that the pronunciation of ’ve is the same as that of of when it is not stressed. This is a common error but it is definitely considered wrong in standard English.

Thanks for the info about French and Spanish governing bodies. TIL

I know right, I know people make careless grammatical mistakes all the time, including me, which is completely fine but people outright thought that “should of” is correct and use it all the time starts to get annoying