The Goose and the Swan

A Certain rich man reared a Goose and a Swan, the one for his table, the other because she was reputed a good singer. One night when the Cook went to kill the Goose he got hold of the Swan instead. Thereupon the Swan, to induce him to spare her life, began to sing; but she saved him nothing but the trouble of killing¹ her, for she died of the song.

1 killing   

n.巨额利润；突然赚大钱，发大财

参考例句：

• Investors are set to make a killing from the sell-off.投资者准备清仓以便大赚一笔。
• Last week my brother made a killing on Wall Street.上个周我兄弟在华尔街赚了一大笔。