Let me copy this example from a conversation I was having in another subreddit:
I've been once in Portugal. I had no problem comunicating with people there speaking a mix of Catalan, Spanish and the little I learnt of Portuguese just before traveling and if people spoke slowly I understood almost 100% of what they said.
The idea was, if a word is different in Catalan and Spanish, better use the Spanish one (Catalan taula, Spanish mesa, use mesa) but pronouce it as if it were a Catalan word, so mèza (em, open e, voiced s, schwa). If it's the same in Catalan and Spanish, use the Catalan one (caixa / caja, use caixa). And it usually works.
So, if I want to ask "Is there an ATM nearby?" in Catalan it is "Hi ha una caixa (caixer automàtic) a prop?", in Spanish "Hay una caja (cajero automático) cerca?" and my fake Portuguese "Hai una caixa (caixero automàtico) cerca?" but cerca not prononced Spanish like therka but Catalan style sèrka (open e, schwa).
from Тавтай морилогтун | Languagelearning http://bit.ly/2QIenr4
via Learn Online English Speaking