A:Good morning,David.How are you?
B:Fine ,thanks,and you?
A:Not very well.
B:what is wrong?
A:I lost my pen.
B:i am sorry,why not ask C,she may know.
A:did you see my pen?
C:no,i did not.but i know D find a pen.
A:thanks.
A:did you see my pen?
D:is it black?
A:yes.it is.
D:i gave it to E,she said she may give to you.
A:did you see E,
F:yes,she is in the classroom
A:did you see my pen?
E:yes.here you are.
