No, you will not use -
"N'est-elle pas?", on its own, for "Isn't she?"
It will be -
Martine, n'est-elle pas malade? = Isn't Martine ill?
Martine est malade, n'est-ce pas? = Martine is ill, isn't she?
Hope this helps!
As I understand it, then yes I believe that this construction is grammatically valid.
Sign in to submit your answer
Don't have an account yet? Join today
Test your French to the CEFR standard