Hi Mike,
I am so sorry that I can't make it with you to Shanghai. I have to attend a big family dinner that I absolutely cannot miss. You know my mother, and how she cares about these silly things. However, I still very much want to go with you. Is there another time that we can go together? I am not free for the weekend next week, but I can go the weekend after that. How does that sound to you? I am really sorry to have to cancel this, I was looking forward to it too. Well, have a nice weekend!
Your Friend,
Hua Li