do italians never say 'lei è nostra vicina'?
The only exception is not using the article is when you're talking about your family members. "Mio padre", for instance.
Cento percento, here, in duolingvo i meet some examples where definite article was omitted in case not of family members, but just humans.
The article is required in this case.
How frequently does an Italian word have both a masculine and feminine version? Is this only and always when referring to people?
for people and animals too...il gatto...la gatta
Some animals, like gatto / gatta. But some animals are neuter-generic, like l'orso.
How about Lei è la vicina nostra?
Is there a way to say she is a neighbour of ours in Italian, using una ?
I wondered this, too. Certainly in English "the" implies that we have only one neighbor.
"È una nostra vicina".
Does not 'vicina' mean close. Is not the correct answer for neighbour 'vicina di casa'
Word Reference has only "'vicino" as a noun, no feminine noun. However as the adjective "near" or "close" there are listed all four endings.
Is there masculine and feminine ending for the word neighbour as well the plural ?
Why can’t you say ‘ il nostro vicino ‘
Why is "i nostri vecina" incorrect? Would "i nostri" be used if it were "vecini" as in loro sono i nostri vecini?