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: 'be city of', Sentence: 'Lahore is Pakistan 's second largest city and the capital of the northeastern province of Punjab .'
city

Given Relationship: 'be commander in', Sentence: 'On issue after issue our hyper-partisan President has abused both the chain of command and his trust as Commander in Chief .'
Commander

Given Relationship: 'be director of', Sentence: 'Steven Chu is a physicist who shared a Nobel Prize in 1997 and the director of the Lawrence Berkeley National Laboratory .'

director