Can 16-year-old students drive to school? No they shouldn’t to drive because they aren’t

问题补充：

Can 16-year-old students drive to school?

No, they shouldn’t to drive because they aren’t serious enough.

A. allow

B. be allowed

C. allowed

D. have allowed

答案：

A. allow

(答案→)B. be allowed

C. allowed

D. have allowed

解析：从上下文可知，他们是被许可的对象，所以用被动语态，选B。