第20题: [单项选择]Questions 11-14 A. It is very near his working place. B. It is a rather crowded residential area. C. It is convenient for transportation and shopping. D. It is the only good position he has in mind. 参考答案:C
第21题: [单项选择]异烟肼片的正常外观是 A. 黄色片 B. 棕色片 C. 棕褐色片 D. 白色片 E. 砖红色片 参考答案:D 答案解析:异烟肼片为白色片。