---There is still a copy of the book in the library. Will you go and borrow       ?---No, I’d rather buy         in the bookstore.

I love junk food very much, but I try to eat ___ only once a week.   

--How do you usually come to school, by bus or by bike?               --       . I walk.

His MP3 is the same as        , but it is more expensive.

 David talked with a friend of ____ on the Internet for a long time yesterday.