the students on duty have clsed the windows改疑问句

the students on duty have clsed the windows改疑问句 on duty 的用法 :the students on duty ___(sweep）the floor when I walked into room in duty,on duty,off duty,duty free区别The students ________ should clean the classroom.A.in dutyB.on dutyC.off dutyD.dutyl free请问这四个选项的意思 The following people will on duty today. on duty on duty 10.The students on duty ______the window,locked the door and left.A．shut B．shutted C．to shut D．shutting为啥选A. The police are duty on the duty on road.这里为什么用are 而不是用is? Today is my on duty for the day. 英语翻译stamp duty on the level,level怎么解释, is duty the on policeman怎么连词成句急 Teachers have the duty for the students` study.同义句Teachers ____ _____ _____ the students` study. on duty today is on duty today who is on duty on duty音标急快啊 the girl in/on red sweater is in/on duty today to the Janitor on duty at the entrance of the Referencing Section.