21The biggest whale is _______ blue whale, which grows to be about 29 meters long—the height of

    ______ 9-story building.  

   A. the; the          B. a; a         C. a; the        D. the; a  

22. I have offered to paint the house in exchange for a week’s ____________.

    A. accommodation       B£®approval    C£®encouragement     D£®assessment