What does the boxing hall signify in the film?

I have answered the question like this, but I have to develop. I need to write 350 words. Thanks for helping me.

I think the boxing hall is a place where Billy can fight his anger and frustration. He’s angry and disappointed with his family because they don’t accept Billy’s choice of dancing ballet. They think it’s just for girls and they prefer him to box because it’s something that has going on for generations. Billy doesn’t use it as a boxing hall, instead, he uses it to practice ballet. It shows that he doesn’t use violence to express his feelings, but with his movements. When he’s dancing he forgets all about the world outside, he doesn’t have to be somebody else.

The ballet coach acts at first very strict and bossy but meanwhile, she changes. She realizes that he’s talented and ballet is a big part of his life. She helps him feel secure and

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