He altered his face all at once.

他变了脸。

He figured the whole scheme at once.

他马上就懂得了整个计划。

The doctor decided to operate at once.

医生决定立刻动手术。

Get him on the blower at once!

马上打个电话给他！

All at once it began to rain.

间下起雨来。

I advise you to own up at once.

我劝你立即坦白。

The president fastened on the idea at once.

总统立即拿定了个主意。

She is hellbent on starting it at once.

她不顾一切地要立刻开始件事。

He lacked the agility to righten himself at once.

他缺乏立即恢复正常的机敏性。

I took the hint and left at once.

我领会了暗示立即离开了。

I can't be in two places at once.

我不能同时在两个地方。

It is expedient that he should retire at once.

他最好还是立刻退休。

Regarding John, I will write to him at once.

至于约翰, 我将立即给他写信。

They set off at once along the lane in pursuit.

他们立即出发沿着小巷。

Mistakes in the printing should be pointed out at once.

刷上的错误应立即予以指出。

As regards John, I will write to him at once.

至于约翰, 我会立即给他去信。

As regards Luther,I will write to him at once.

至于卢瑟,我会立即给他去信。

The committee judged it better to start the work at once.

委员会认为最好立即开始项工作。

Any infectious disease must be notified at once to the Health Ministry.

出现任何传染病都必须马上通知卫生部。

I don't want ifs and buts; swallow your medicine at once.

我可不听你泡蘑菇, 马上吞下你的药。