Dropping "du" when using "ni..ni".

Question

My on-line instructor - a native French speaker from Normandy - says that it is totally incorrect to drop the "du" when using "ni..ni". I had learned in one of your lessons that I should keep the articles le, la, les but drop "du". Which one of you is correct?

Accepted Answer

Ruth
Many sites on the web support the information in the lessons on KwizIQ. As an absolute statement, your tutor's comment seems to be contrary to most information on this that I have come across.
Below are two links:  
https://www.cliffsnotes.com/study-guides/french/french-i/french-i-articles/partitive-articles
https://www.carleton.edu/french/resources/language-tools/grammar/articles_negatives/
Having said that I have seen a couple of places where (reportedly) native speakers wrote on a discussion site that they would use the indefinite/partitive articles.
My wife is French - she fully agrees with the dropping of the article as is taught here. As I know from others in the family, just as in English, not every native speaker has perfect grammar (whatever that is)!