34. Unlike watching TV, reading is a highly active process (过程)________ it requires attention as well as memory and imagination. (A) until (B) but (C) unless (D) for

29.They _______ on the program for almost one week before I joined them, and now we________ it as no good results have come out so far. (A) had been working; are still working (B) had worked; were still working (C) have been working; have worked (D) have worked; are still working