swan song

swan-song的词性：
n.（名词）

1. A farewell or final appearance, action, or work.
最后作品：最后或告别的登台、演出或作品

2. The beautiful legendary song sung only once by a swan in its lifetime, as it is dying.
天鹅之歌：传说天鹅一生中所唱唯一的、也是临死前唱的美妙歌曲

swan-song的词源：

3. [From the belief that the swan sings as it dies]
[来自于天鹅临死之歌的信念]