21. The party last night was ____ success. We sang and danced until it came to _____ end at 12:00.
A. A; an B. a; the C. the; an D. /; an
22. Riding bikes has advantages __________ driving cars ________ many aspects.
A. above; in B. over; in C. on; on D. with; on
23. Two _____ died of cold last winter.
A. scores of old people B. score of old people C. scores of old peoples D. score of old peoples