I was busy at work so I didn't think about what needed doing.

我忙于工作，便没有考虑需要做些什么。

youdao

Explain why you think this person is a good parent. If you were a parent and you were busy at work, would you take care of your children on your own or hire a babysitter.

解释一下为什么你认为这个人是一个好家长。如果你是一个家长并且忙于工作，你会自己照顾你的孩子还是雇一个保姆。

youdao

The past month has been really busy at work.

上个月工作实在是忙。

《牛津词典》

When the legislators are busy at work, there is also a negative effect on equities markets.

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Marvel was busy at work on The Avengers and Iron Man 3 and Paramount was on board to distribute those films.

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While many of us were opening presents and having our fill of mulled cider, NASA's trusty Curiosity rover was busy at work capturing panoramic views of Yellowknife Bay, a shallow area of unusual terrain on the Red planet.

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