Its wrong to not attend rehearsals...but there might be a reason to why she is not attending it. Maybe she fears the people in so someone visits her out and teaches her. Theres always a positive side to a terrible problem If you are participating in the competition, why don't you attend the practices?? If you don't practice with your group, you can't expect to get the steps right and in coordination! You should understand that in a good group dance, all the steps are coordinated and perfect, and for that you need heaps of practice. Otherwise even if you look very good at first, as the dance will progress, you'll look like a clown! I'm not joking. Attend ALL the practices so that you're perfect and you can set the stage on fire             According to me as I friend I would personally go and tell her that attend the practices regularly because of u we aren't able to form the group formations and a lot of time was wasted it's better if u come regularly . If she doesn't takes it seriously then go along with ur frnds and give her the last warning either come to the practises or leave this dance . And if the situation worsens then go and complain to the concerned teacher       
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