"He lives between Italy and France."
Translation:Vive tra l'Italia e la Francia.
Countries have artcles but lose them when introduced by in but get them back when modified some way:<pre>
Amo l'Italia (I love Italy) Vado in Italia (I go to Italy) Vado nell'Italia meridonale (I go to Southern Italy)</pre>
this detail was never explained earlier but we are expected to know it (?!) How?
By reading my comment. :-). But seriously you need a grammar and a dictionary - no way is Duo enough on its own. Also I think that you go in to large areas like countries and regions but a to smaller ones like towns.