He believed some of his greatest music had gone into the opera.

VOA: special.2009.02.15

Well, yes, with opera of course, but the other eighty percent is purely instrumental music.

没错,歌剧中是有歌词的,但其他百分之八十的古典乐都是纯器乐

耶鲁公开课 - 聆听音乐课程节选

He also wrote an opera, and music for piano and orchestra.

VOA: special.2009.02.15

"We've played pop music. We're playing "Phantom of the Opera."

VOA: special.2010.06.21