二.单项选择 (20分)
21.What great fun it is to listen to good music!
A. a, an B. /, / C. a, a D. /, an
22.------When did the terrible earthquake in Japan happen?
------It happened __________1:46 __________the afternoon of March 11, 2011.
A. on, in B. at, on C. at, in D. on, on