Detailed Instructions: 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: 'Chavez was in Rio de Janeiro to attend a two-day summit of the Mercosur trade bloc , of which Venezuela is a member along with Argentina , Brazil , Uruguay and Paraguay .', Argument/Subject 1: 'brazil', Argument/Subject 2: 'mercosur'
A:
be member of