8Bunit3-4月考试题,中考题型,二、单项选择(15分) 21. He wrote _____ letter to his parents. A. 3000-words B. a 3000-word C. 3000-word D. a 3000-words 22. My brother’s never been late for work,______________? A. is he B. isn’t he C. has he D. hasn’t he 23. One of the club activities ________ by Mr Smith. A. is holding B. are held C. is held D. holds 24. This kind of medicine ________ in a dry and cool place. A. keep B. kept C. must keep