1、Dear Tom，

  Thank you for asking me to visit your farm．I’d love to，but I’m afraid I can’t．Today is Friday．I’m going to see my grandparents this evening．Tomorrow morning I have to help my father work in the garden，and in the afternoon I am going shopping with my mother．On Sunday I have to study for the Chinese test．In the evening I’m going to the concert with my friends．Let’s make it some other time．

Write soon．

Yours，

                                                                   John