I am really sorry that I opened your letter by mistake. 如何回答

I am really sorry that I opened your letter by mistake. 如何回答 -----I am sorry to take your pen by mistake. i'm sorry ,i took your english book by mistake 回答 英语翻译My love;I am sorry that I am just answer your letter now Sorry,I have taken your book by mistake.A.That's all right B i really am sorry I am____( true) sorry . took your umbrella by mistake. ---Sorry.I have taken your book by mistake.---_________. I am afraid I_____ your file by mistake.（take） i am sorry for that 的回答 I'm sorry that I forgot _____(send) your letter. am also that your mistake begins but,I let a mistake last ,i