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.

Ex Input:
Sentence: 'The current President , Dr. Peter Fong , is the Head of the Centre for Executive Development of HKU SPACE and former Executive Vice President and Professor of Asia International Open University .', Argument/Subject 1: 'president', Argument/Subject 2: 'executive'

Ex Output:
be head of

Ex Input:
Sentence: 'London is both the capital of England and the United Kingdom and it serves as the headquarters for the Royal Family .', Argument/Subject 1: 'london', Argument/Subject 2: 'england'

Ex Output:
be capital of

Ex Input:
Sentence: 'Thanksgiving Day in the United States is still celebrated as an important historical holiday .', Argument/Subject 1: 'thanksgive', Argument/Subject 2: 'unite state'

Ex Output:
be holiday in