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John: Where have you been? You missed the announcement about the music festival.

Frank: I was at the teacher's office. Music festival?

John: Yes, it's going to be  in the school hall. Frank, you can play the violin.  playing it at the festival？

Frank: Well, I'd rather play the piano. I can playMojito. What about you, John?

John: Actually, I don't have much . I'd prefer just to do some voluntary work. I can  tickets.

Frank: So can I guess that the aim of the festival is to  ?

John: Yes. All of the money will go to charity.

Frank: Well, if it's for a good cause, everyone should take part!