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: 'I was editor of Surfer magazine , and Richard Nixon was president of the United States .', Argument/Subject 1: 'nixon', Argument/Subject 2: 'unite state'
be president of

Sentence: 'They made Israelis Threaten Iran And Iran threaten Israel and I said it is all bluff and on and on and on .', Argument/Subject 1: 'iran', Argument/Subject 2: 'israel'
threaten

Sentence: 'Audio playback of mp3 files worked much better with impressive sound quality .', Argument/Subject 1: 'audio', Argument/Subject 2: 'mp3'

file to