We all think _________ impossible that he should be so impolite.

----Is it my age __________ the boss minds?  
----I’m afraid not. He will consider __________ necessary to have an experienced assistant.

I have done much of the work. Could you please finish ______ in two days?

We feel         our duty to make our country a better place.

The CDs are on sale! Buy one and you get        completely free.

-Would you get me a bar of chocolate from the kitchen,dear?
-          one?                                        

-Would you get me a bar of chocolate from the kitchen,dear?
-          one?                                        

To stay awake, he finished a cup of coffee and ordered ______.

—Silly me! I forget what my luggage looks like.
—What do you think of _____ over there?

---Which one will I choose?
---Well, you can take _______ of them; I’ll keep none.