I am grade 4 viola and my friend (grade 7 violin) does GCSE music and asked me to play in his ensemble piece.
Naturally, being grade 4 viola I wasn't his first choice. However, the sixth year he asked to play the viola part is on study leave and can't come in, that's when he turned to me.
The piece is bohemian rhapsody and whilst it is simple enough, I simply cannot play the fast part of the piece with all the shifts.
I am inexperienced as I wasn't able to join string group or orchestra this year and feel very insecure about my musical ability.
I might be able to get the hang of it by next week but I have about 6 exams between now and then so won't have a lot of time to practise.
Should I tell him I can't do it or should I just keep working at it and risk playing atrociously on the day?
If I should cancel what should I say to him as I really don't want to let him down.
(Btw this performance is a mock of the real performance but I still value my integrity)
Thank you