参考答案：许多城市都存在贫民区，住在那里的人在危险与贫困中煎熬度日。漂亮的建筑和充满活力的夜生活固然是城市的一面，但城市中也同样存在不平等、拥挤和贫困的问题。

解析：
Many cities have slum areas or ghettos, where people live in dangerous or destitute conditions. The beautiful architecture and vibrant nightlife are one face of the city. But cities also have problems of inequality, crowding, and poverty.