be busy with A. 忙于做某事 B. 忙于做…… C. 忙于…… D. 繁忙

The correct way to express "be busy with" in Chinese depends on the context. Here's a breakdown:

A. 忙于做某事 – This means "to be busy doing something," with "某事" (something) being a placeholder for whatever specific task you're referring to.

B. 忙于做…… – This is similar to A but leaves the task more open-ended, implying the person is busy doing something (the ellipsis indicates something unspecified).

C. 忙于…… – This is an even more general phrase, where you're simply saying "busy with" without specifying exactly what the task is. It's often used in more abstract contexts.

D. 繁忙 – This means "busy" or "occupied" in a general sense, but it doesn't have the same structure as the others. It's more of a state of being busy and isn't typically used with "doing something."

So, if you want to say you're busy doing a specific task, A. 忙于做某事 is the best choice!