degenerate into〔to〕 (v.+prep.)
堕落为…,降格为… become lowered, morally or in quality to sth
▲degenerate into〔to〕 sth
The conversation degenerated to a personal attack.谈话变成了人身攻击。
The wide paved road degenerated into a narrow bumpy track.铺好的宽阔道路渐渐变窄,成了一条崎岖不平的小径。

用作不及物动词
▲S+～(+A)
His health degenerated with disease and old age.他的健康随着疾病和年老而衰退。
He denied that some young people today were degenerating.他否认现在某些青年在堕落。

用作定语
▲～+n.
Just what do you mean by “degenerate art”?你说“颓废艺术”是指什么?
用作宾语补足语
▲S+V++O+～
 Will too much freedom make them degenerate?太多的自由会令他们堕落吗?

degenerate也可用作名词,意思是“堕落者”。例如:
He was a degenerate.他是个道德败坏的人。