While trying to finally nail the adjective endings I stumbled upon this article suggesting a simplified way of learning it:
But either I do not understand their 2nd principle or the entire idea falls apart while dealing with an example like this:
Ich bin im rheinhessischen Dorf Wiesoppenheim aufgewachsen.
Okay, that's a dual preposition and dative. If I understand the article correctly dative results in an
im (in dem) but then where does the
en ending in
rheinhessischen come from?
Can someone please clarify?
Edit: Also I don't see how this unified table in the article will work with plurals. For instance for this example (plural and nominative):
Die anderen Kinder sind bösartig.
It would suggest
e ending while the correct one is
en. Does it also fall back to the 2nd principle where
Die takes a case ending
e? Where does the
en came from again?