zhè / tiáo / dì / tiě / zhǔ / gàn / xiàn / lián / jiē / le / shì / zhōng / xīn / hé / jǐ / gè / zhòng / yào / shāng / yè / qū

这条地铁主干线连接了市中心和几个重要商业区。

This main subway line connects downtown with several major business districts.