Given the task definition and input, reply with output. 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 island in', Sentence: 'Sri Lanka , an island country on the Indian Ocean with a population of over 18 million , has a mixed religious community including the dominant Sinhalese Buddhists and minorities of Muslim and Tamil .'
island