The light in his office is still on. He must be at work now.

他办公室的灯还亮着。他现在一定在工作。

youdao

I'll be at work by sunrise.

日出之前我就开始工作了。

youdao

You seem happy to be at work.

你看起来非常乐于工作。

youdao

Their job might be fun, or they like their employer and the other people at work.

VOA: special.2009.10.18

It's eight thirty. I have to be at work at nine.

都八点半了。我必须九点钟到公司。

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So that, to think nothing is something you have to work at; it's something that you can be preoccupied with.

所以脑子里一片空白,也是需要你努力的事;,需要全神贯注的事。

耶鲁公开课 - 1945年后的美国小说课程节选

On the other hand, a peculiarly British set of conditions may be at work.

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This is only a micro strategy for those that have to be at work through year-end.

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"It's just unfortunate that he has to be at work when we're celebrating, " she said.

CNN: Retail employees fight 'Black Friday creep'