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.
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Question: Given Relationship: 'be president of', Sentence: 'Now George W. Bush is the President of the United States .'

Answer: President


Question: Given Relationship: 'be key to', Sentence: 'As present processes are thought to explain all past events , the Uniformitarianism slogan is " the present is the key to the past . "'

Answer: key


Question: Given Relationship: 'be island of', Sentence: 'Lesvos or Lesbos is the third largest island of Greece and has a long history that goes back more than 3.000 years .'

Answer:
island