– It is said that Frank is very rich and is always changing his private cars .What is he?–_______ of a manager, I am not sure.

Charles Darwin, a young man just out of university, knew perfect well that he had to depend on _____ when he set out on a voyage of discovery around the world. 

____ wants to stay in a hotel has to pay their own.

My father always warns me that there is no such thing as a free lunch because we can’t get _________ for nothing．

Of all the books on the desk,       is of any use for our study.