那个曾经繁荣的社区如今已堕落为一个犯罪猖獗的贫民窟。

The once thriving neighborhood has ___degenerated into a crime-ridden slum.

那个赌徒已经彻底堕落，丧失了所有的廉耻之心。

The gambler has become a complete ___degenerate, losing all sense of decency.

如果长期缺乏锻炼，人的身体机能会逐渐退化。

Without regular exercise, one's physical abilities will ___degenerate over time.