Dear Tom,
  It’s a long time since we met last time and I miss you very much. hanks for your invitation. However, I regret to tell you that I can’t travel o America this winter holiday for some unavoidable reasons.
  First of all, it’s the coming of the Spring Festival that makes me refer to stay at home rather than take a travel to America. As far as
  we Chinese are concerned, the Spring Festival is a family time treasured
  by us all. What’s more, the College Entrance Examination is coming. So
  significant is it to me that I will attend some tutorial classes during this
  winter holiday for some of my weak divisions. Taking all the above
  factors into consideration, I have to say sorry again
  Anyway, shall I make it after the Exam? I will appreciate it if you
  can be my guide at the time. Yours
  Li Hua