Although there are no classes in the afternoon now no student go out of school without t

问题补充：

Although there are no classes in the afternoon now, no student go out of school without the head teacher’s permission.

A. will

B. must

C. may

D. shall

答案：

A. will

B. must

C. may

(答案→)D. shall

解析：考查情态动词用法。当shall用于第二第三人称时，表示命令，警告，允诺，威胁，法律，规范。根据the teachers permission可知。