Dear XX,
How is everything going? I am very well these days and busy preparing the mid term exams.
Could you do me a faver to buy a English grammer book for me? Beacause I am too busy to go shopping.I need a book with explains, examples and excersises. I will pay you next week.
Come to my home when you have spear time.Missing you so much!
Best wishes!
Yours,
XXX