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.
Input: Sentence: 'Robert was a proud U.S. Veteran who served as a Merchant Marine during World War II and in the U.S. Army during the Korean War .', Argument/Subject 1: 'robert', Argument/Subject 2: 'world war ius'
Output:
be veteran of