A:I'm sorry, but I can't find the book you lent me. I guess I have lost it.

A:很抱歉，我找不到你借给我的那本书了。我想我是给丢了。

B:Don't worry about it.

B:别担心了。

A:I really feel bad about it. Let me buy you a new one.

A:对此我真的很抱教。让我再给你买本新的吧。

B:No. Don't be silly. I wouldn't dream of letting you do that.

B:不用了，别这么傻。我不会让你那么做的。