When to use "andare a" vs "andare al, allo, alla, ai, agli, alle" vs "andare in"?

Question

I'm trying to understand the rules but I don't seem to find a proper pattern.The main problem is my Spanish and French conflict with Italian...Io voglio andare a USA?Io voglio andare ai USA?Io voglio andare in USA?In Spanish I would use a, in French I would use aux, which is ai... but what about Italian?

Answer 1

In Italian it would be "Andare negli Stati Uniti".

For countries we use the preposition IN, countries also need the definite article (L'ITALIA, LA FRANCIA, GLI STATI UNITI...)

Therefore

IN+GLI = NEGLI

From my experience knowing when to use A and when to use IN is one of the hardest thing to learn for students, so don't feel bad!! CIAO!!