The new teaching building before the new term begins.A. must be finishedB. must finishC.

问题补充：

The new teaching building before the new term begins.

A. must be finished

B. must finish

C. must finished

D. must being finished

答案：

(答案→)A. must be finished

B. must finish

C. must finished

D. must being finished

解析：句意：新的教学大楼必须在新学期开始前完工。结合语境可知本句主语为动作对象，故用被动语态，选A。