—There is still a copy of the book in the library. Wall you go and bottow          ?—No, I’d rather buy         in the bookstore. 

The old couple preferred a flat in a small town to ______ in so large a city as Chongqing．

The role change from husband to father, although difficult, doesn’t seem so great as _____    from wife to mother.

Did you do_________ last weekend?

—How many students are there in the classroom?—_________. They are all in the lab.