on duty

There were 2,250 policemen on duty in and around the stadium.

在体育场内及周边有2,250名警察在值勤。

The man on duty rang an alarm.

值班员发出警报.

The striped band round a policeman's sleeve is to signify that he is on duty.

警察袖子上的袖标标明他正在执勤.

I was on duty during the morning watch.

我值早班.

Extra staff had been put on duty.

编外人员已经就职。

The nurse on duty was fearful that the patient should get worse.

值班的护士担心病人的病情会恶化.

There was a comfortable-looking clerk on duty, tapping away on a manual typewriter.

有个神态安适的办事员在当班，在手动打字机上啪嗒啪嗒地打着字。

The night watch comes on duty soon.

值夜班的人很快就要来值班了.

Half the garrison are on duty.

有半数卫戍部队在执勤。

Six are on duty.

六个人在值班.

A policeman must not smoke while he is on duty.

警察当班值勤时不得抽烟.

The officers on duty were visibly overcome, many of them in tears.

那些值班的官员明显不能自持, 许多人都流出了眼泪.

A policeman has to keep on his toes all the time he's on duty.

警察在执勤时必须时刻保持警覺.

He's on duty twenty-four seven.

他不分昼夜地天天上班。

We'll take our turn on duty at 1 p.m.

我们下午一点接班.