Would you correct my letter for me please

[M Hassan]

dear sir
I would like to complain about a driving test which I given 5th of april 2011 for which the instructor failed me saying I don't understand English. my test was for forty minutes he took only twenty minutes and it cost me £80 i don't think I misunderstood him what ever he asked me to do I did if I get my refund I will apply for another test & it will be proven that i do understand English thankyou
Your sincerely
Mr hassan

[luschen]

Hi, I am a native speaker and my version sounds adequate to me.

dear sir
I would like to complain about a driving test which I given 5th of april 2011 for which the instructor failed me saying I don't understand English. my test was for forty minutes he took only twenty minutes and it cost me £80 i don't think I misunderstood him what ever he asked me to do I did if I get my refund I will apply for another test & it will be proven that i do understand English thankyou
Your sincerely
Mr hassan

Dear Sir,

I would like to make a complaint about a driving test which I was given the 5th of April, 2001, for which the instructor failed me saying I don't understand English. The £80 test was supposed to last forty minutes but he took only twenty minutes. I don't think I misunderstood any of his instructions and I performed all that he asked of me. Please refund the testing fee, which I plan to use for another test where I can prove my command of the English language.

Yours sincerely,

Mr. Hassan