opera house的复数形式怎么写？

n.歌剧院...

opera house的音标：opera house的英式发音音标为：['ɔpərə haus]opera house的美式发音音标为：['ɑpərə haʊs]...

The following year she joined the Royal Opera House.次年她加入了皇家歌剧院。Young conductors earn their spurs in a small orchestra or opera house.年轻的指挥家们在小乐队或小歌剧院里崭露头角。The Opera House is decorated with the Hungarian national colours...