I'm Having Trouble With Feminine Nouns:
When you change a feminine noun from indefinite to definite, what does it change to? Do all feminine nouns follow the same rule as ei jente changing to jenta?
Feminine nouns inflect in the following way: ei jente --> jenta / ei kvinne --> kvinna / ei bok --> boka. If you're doing to use the indefinite article, ensure you inflect the noun in the feminine manner. Using one and not the other would make little sense. Are you speaking with the third gender or not?
To maintain consistancy I would recommend you do not mix up the masculine indefinite article with the inflected feminine definite article. For example:
ei jente = jenta en jente = jenten en jente =/= jenta ei jente =/= jenten
We all know that it is possible to speak Norwegian with only 2 genders (masculine and common). However, I would recommend that if you're gonig to speak with three, make sure that they are distinct from each other.