Actually, I'm busy at the moment—can I call you back?

说实在的，我这会儿正忙—我可以给你回电话吗？

《牛津词典》

I'm afraid the doctor is busy at the moment. Can he call you back?

恐怕医生现在没空。让他给你回电话行吗？

《牛津词典》

Sorry, I'm busy at a the moment. Can I call you back later?

对不起，我现在正忙着，待会再给你打过去好吗？

youdao

He called the emergency management agencies including the state units and FEMA. They were too busy to call back.

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Patients requiring routine appointments or test results are asked to wait a few days or call back at less busy times.

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And when I call them, they are often busy, and we get a message saying that we have to call back later on.

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