metropolitan area的用法和样例：
例句
- The capital and largest city of Belgium, in the central part of the country. Officially bilingual(Flemish and French), it became capital of Belgium in1830. Metropolitan area population, 2,395,000.
布鲁塞尔比利时首都和最大城市，位于比利时中部。官方使用双语制(法兰德斯语和法语)。1830年成为比利时的首都。人口2,395, 000
