21.The cakes which the restaurant served were delicious. The customer would like _____ third one because _____ second is rather too small.
A. a; a ¡¡¡¡¡¡¡¡¡¡B. the; the          C. a; the ¡¡¡¡¡¡¡¡¡¡D. the; a

22. —Where have you been?

—I got stuck in the heavy traffic, or I _____ here earlier.

A. had arrived¡¡¡¡ B. was            C. would come¡¡¡¡D. would have been