【正确答案】[范文]
   投诉信
   
Dear Mr. Manager,
   I'm very sorry to complain to you about the poor service in your store.
   The day before yesterday when I was passing your shop, I happened to find shoes in the shop window which I liked very much. When I found the shoes she showed me was too big, I asked her to show me a smaller one, but she refused.
   I hope that she could make an apology to me and you will make her understand how to serve customers.