Don’t touth anything unless .A. to be allowedB. allowedC. to be allowingD. allowed to

问题补充：

Don’t touth anything unless .

A. to be allowed

B. allowed

C. to be allowing

D. allowed to

答案：

A. to be allowed

(答案→)B. allowed

C. to be allowing

D. allowed to

解析：句意：不要触摸任何的东西除非被允许。这里用了状语从句的省略。完整的句子是：unless you are allowed to touch，当主从句的主语一致的时候，可以省略从句的主语和be动词，选B。