21. As the busiest woman in Norton, she made_____ her duty to look after all the other people’s affairs in that town.
A. this B. that C. one D. it
22. Greenhouse phenomena would cause ______ rise in sea levels worldwide and change ______ weather on the earth.
A. a; the B. the; 不填 C. a; 不填 D. 不填; the
23. ________work has been done to improve people’s living standard.
A. Many B. A great many C. A great deal of D. A large number of
24. —How's everything with you?
— .
A. Fine, thanks B. It's all right
C. Thank you very much D. I'm very well
