As teacher you must believe that you can make difference to the lives of your students

问题补充：

As teacher, you must believe that you can make difference to the lives of your students.

A. a; 不填

B. a; a

C. 不填; 不填

D. 不填; a

答案：

A. a; 不填

(答案→)B. a; a

C. 不填; 不填

D. 不填; a

解析：句意：身为教师，你们必须坚信你们能够影响学生的一生。第一空填a，泛指“一位老师”，第二空填a，make a difference“有影响，有差别”，所以选B。