Because my editor here at guardian.co.uk/books is unaccountably unwilling to allow italics in my submissions, I suspect you will be unable to understand the following: “You can’t teach creative writing.”
The reason for the sentence’s ambiguity is that, unitalicised and out of context, it is unclear how the stresses work. It might mean any of the following:
You can’t teach creative writing, but I can.
(As if said to oneself): I can’t teach creative writing.
You can teach other sorts of writing, but not creative writing.
You can teach other sorts of creative stuff, but not writing.
I could go on …