Given a sentence and two mentions from the text (arguments), indicate a phrase (a verb or noun phrase) that describes the relationship between the provided arguments.
Q: Sentence: 'Cross over to Latin America and Spanish is ubiquitous apart from Brazil where Portuguese is the mother tongue and a fairly easy language to master but not much use for either worldwide business or travel .', Argument/Subject 1: 'portuguese', Argument/Subject 2: 'brazil'
A:
be language of