I want to say sorry to you because I missed the book you borrowed to me last week. I remember I put it on the book shelf after I read it Last Wednesday. Today I looked for it on the shelf, but could not find it. I asked my mother whether she placed it elsewhere when she cleaned the shelf. But she said no. I did not lent it to someone else. So it must be at my home, only we do not know where exactly it is. I will try to look for the book and tell you once I find it. Please do not worry. If I cannot find it, I will buy another book for you.