Up till now, the "is niet" or "is geen" variations seem to have been interchangeable, but this time I wasn't allowed "Zij is niet een kunstenares" - is there a rule here?
If niet is associated with een, as in your example, it should be geen.
I got the feeling that geen was numerical (like zero quantity) vs niet was not. But een is a number.....
Een is the article, één is the number.
why is 'geen' used here when you usually wouldn't use an indef. article with a career description anyway?
There is a female form of artiest : 'artieste'. Why is it considered a typo?
Artieste is a different job. A kunstenares makes art, an artieste performs on stage