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.

Example Input: Sentence: 'Eglin Air Force Base and Patrick Air Force Base held Memorial Services on the 23rd and The White House Commission on Remembrance held a Memorial Service at Arlington National Cemetery on the 25th for the families .', Argument/Subject 1: 'service', Argument/Subject 2: 'arlington national cemetery'
Example Output: be hold at

Example Input: Sentence: 'But even though it 's the poorest country in South America , Bolivia is surprisingly self-sufficient with ample supplies of oil , natural gas and other natural resources .', Argument/Subject 1: 'bolivium', Argument/Subject 2: 'south america'
Example Output: be country in

Example Input: Sentence: 'Flock is built on top of Firefox and the team have been working hard over the last couple months to upgrade Flock to the new Firefox 3 base .', Argument/Subject 1: 'flock', Argument/Subject 2: 'firefox'
Example Output:
be build on