This was supposed to be the libretto for an opera.

这押韵版的《失乐园》本来是用作歌剧剧本的。

耶鲁公开课 - 弥尔顿课程节选

And it begins with an auctioneer selling various articles from the old opera house.

刚开始的时候就是一个拍卖家在卖老歌剧院的各种物品。

歌剧魅影 - SpeakingMax英语口语达人

I think she was also an opera singer.

我觉得她可能还是一个歌剧歌手。

麻省理工公开课 - 电影哲学课程节选

Yes, she was an opera singer as well.

对，她也是一个歌剧歌手。

麻省理工公开课 - 电影哲学课程节选