Given the task definition and input, reply with output. 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.

Sentence: 'Iran , Saudi Arabia , Algeria , Indonesia , Iraq , Kuwait , Libya , Angola , Nigeria , Qatar , Venezuela and the United Arab Emirates are 12 members of OPEC .', Argument/Subject 1: 'venezuelum', Argument/Subject 2: 'opec'
be member of