I'm very sorry to say that I lost your dictionary last weekend.Although I argued with her,I felt sorry for her.It took her fifty yuan to buy the dictionary.She often uses her dictionary to study her lessons.She is so good a student that she can usually help me with my lessons.With the help of her,I have made much more progress in my study than before.I must thank her for that kindness.
I must buy the dictionary back and I will return it to her.
Yours xx