People would watch the operas, ballets, and plays more often for entertainment in the 20th Century because the operas, ballets, and plays weren't just for wealthy, high class people anymore. Nearly anyone would be allowed in to the operas, ballets, and plays. This is also when the operas, ballets, and plays started to evolve to be what we know now. Ballet was especially flourishing during this time. Many of the most famous ballet dancers were from the 20th Century.
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