A:Excuse me,Kangkang._Is that my sharpener?___
B:sorry.It's my sharpener.
A:__Where is mine?___________
B:Is it in your bag?
A:__No,I don't think so._But my pencil case is in it.
B:__Have you left it somewhere else?________
A:No,my pencil is in my pencil case .
B:what's that behind your pencil case?
A:It's a book.
B:Book?What's that in it?
A:Oh,__That's my sharpener,___Thank you.
B:that's all right.
题中有点问题,我改了.