Her mother is busy cooking in the kitchen. be busy doing sth.

忙着做某事（她的母亲正在厨房忙着做饭。）

youdao

Between the commitee's report in April and then, Mr Howard will be busy doing deals with Mr Harradine and others in the existing Senate to get his original plan through, with a tax on food and all.

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Mr. Buffett argues that normal investors should not necessarily be able to find out what professional investors are doing, especially while they are still busy doing it, reminding me a lot of the Not in My Back Yard situation.

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And you could be distressed even though you're not all that busy -- if you just hate what you're doing.

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