Definition: In this task, you are given triplets. Each triplet is in the form of [subject, predicate, object]. Your task is to generate proper sentence that utilizes these triples. The objective is to construct a sentence that (a) captures the facts specified in the triples and (b) is a well-formed sentence easily understandable by a human. All triple values need not be used directly in the sentence as long as the facts are adequately captured.
Input: [['Beijing', 'URBAN_AREA', '19,295,000'], ['Beijing', 'BUILT-UP_AREA', '19,785,051']]

Beijing's urban area has a population of 19,295,000, but its built-up area has a population of 19,785,051.