1. 选词填空

mine  yours  His  they  your

1. （1） He is very lazy. bedroom is very dirty.
3. （2） —Whose book is this？

   —It's .

5. （3） —Is this bedroom？

   —Yes, it is mine.

7. （4） —There is a cap over there. Is it ？

   —No, it isn't my cap.

9. （5） —Are they yours？

   —No, aren't.