Dear XXX,
I am so sorry that I didn't respond your letter promptly yesterday for I was a little busy with my work.Thanks alot to your snacks which prepared for me,it was so delicious.You said that you would come to here in National day,I am sorry to tell you that because of the holiday,I must to work at weekends before the National day,and also,I don't have time to play with you in this holiday for my grandmother‘s birthday is coming.So,would you mind to change the time when to come here,and you said you would stay for three days,I wanna know whether it including the time you spend at the airplane or not.
My families are looking forward to your coming,but my home is a little bit small,if you don't mind,you can live with me or I can help you to book the hotel,Waiting for your good news .