[esafak]

What if the model simply substitutes synonyms here and there without changing the spirit of the material? (This might not work for poetry, obviously.) It is not such a simple matter.

[Workaccount2]

It's pretty simple, you are absolutely allowed to do that, and it's been done forever.

Imagine having the copyright claim to "Person's family member is killed so they go and get revenge".

[esafak]

So I can duplicate a book and change and word or two and sell it? That does not sound right.