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 city in', Sentence: 'Milan hotels -Milan is either Italy 's second or first city , depending on who you ask .'

Answer: city


Question: Given Relationship: 'be service of', Sentence: 'See a list of publications by Mayo Clinic authors on mitral valve disease on PubMed , a service of the National Library of Medicine .'

Answer: service


Question: Given Relationship: 'bless of', Sentence: 'And God bless the United States of America" .'

Answer:
bless