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.

Given Relationship: 'attack', Sentence: 'The U.S. has pledged to warn Israel of any attack against Iraq .'
attack

Given Relationship: 'become', Sentence: 'But how did the Apostle Paul become a Christian and an Apostle ?'
become

Given Relationship: 'be son of', Sentence: 'Background and early career Hannibal Barca was the son of Hamilcar Barca and his Iberian wife .'

son