Detailed Instructions: From the given sentence, extract the phrase (often noun or verb) that carries the given relationship. The generated phrase should be present in the sentence.
Problem:Given Relationship: 'be president of', Sentence: 'A unique book with a priceless legacy that will nourish your family in body and spirit and the Foreword is by US Senator and soon to be the 44th for president of the United States , Barack Obama .'
Solution:
president