Dear Peter,
Thankes for your letter. I am glad you passed your history test.
I was sorry to hear about the argument you had with your parents summer holidays. I know it is boring to be at home in summer holidays but don't worry all will be fine.I will give you some advices.
I disagree wiyor parents because in summer holidays people don't stay at home. If I were you I'd try to tell with your parents. I'd say that I am to old and can go on holiday with my friends only. If it willn't help I'd invite parents with me. Say it for your parents I think they will understand you.
Anyway, keep smiling whatever happens! I'd better go now as I've got loads of homework to do.
Write back soon!
With the best,
Denis