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: 'approve', Sentence: 'Some groups of mechanism of Adderall is I want to make it ca n't take the of it There are Donald fda approved generic viagra sildenafil citrate the commercial in prison anyone battling relaxed at the end product did n't stick .'
approved

Given Relationship: 'become', Sentence: 'Elected Vice President in 1944 , Truman became President upon Roosevelt 's sudden death in April 1945 and was immediately faced with the problems of winding down the war against the Axis and preparing the nation for postwar adjustment .'
became

Given Relationship: 'be chairman of', Sentence: 'Alan Greenspan , chairman of the Federal Reserve , has entered the debate , denouncing protectionist pressures .'

chairman