Dear Alice,
   Thank you to invite me to your birthday party. I afraid that i can't be able to come. We have many things to do this week. Boss asked me to work overtime. I promise to do so I and he have to keep the promise. I wish I can go to the party. If I'm there, all of us will have a good time. I thought about you when I type this letter. I hope your party will be a success. I wish you have an happy day.
                                                                                                                                                                                   Love,
                                                                                                                                                                                 Dorothy