---Is ______ book on the desk?

---No, it's ______ the sofa．

1. A.
   your, on
2. B.
   you, in
3. C.
   my, of
4. D.
   my, for

一Is ______ book on the desk ______ useful one?

一No, it isn’t．

A．the；an        B．the；a           C．a；the        D．the；the

---Is______ book on the desk yours?

---Yes, it's______ my book．

A．the, a        B．the, the         C．the, /         D．a, the

---Is ________book on the desk __________useful one?

---No, it isn’t.

A．the; an        B．the; a         C．a; the        D．the;/