问题补充:
What worried the woman most was to visit her sick son in hospital.
A. not allowing
B. not being allowed
C. not allowed
D. having not being allowed
答案:
A. not allowing
(答案→)B. not being allowed
C. not allowed
D. having not being allowed
解析: 考查非谓语动词作表语。因为the woman和allow之间是动宾关系,所以要用doing的被动式。所以选B.