问题补充:
In the school hall, where a meeting , some students are busy preparing for it.
A. is held
B. has been held
C. is being held
D. is to be held
答案:
A. is held
B. has been held
C. is being held
(答案→)D. is to be held
解析:考查时态。句意:在在要举行会议的学校大厅里,一些学生们正在忙碌的为此做准备。结合语境可知定语从句中描述的是将来的动作。不定式做表语可以表示计划打算进行的动作,故选D。