一般有两种形式，分别是：be busy doing sth；忙于做某事；be busy with sth；忙于某事；busy后面如果+动词，则要用动名词形式，即be busy doing sth。忙于做某事。若是直接加名词，则用介词with连接，即be busy with sth。
相关介绍
例句：
Not to hide the truth, Mistress Hester, my thoughts happen just now to be busy with the gentleman.
咱们不说假话，海丝特太太，这会儿我刚好正忙着在那位先生身上转着念头。
He pretended to be busy with some work.
他假装忙着什么事。
Be busy with I am busy with my homework.
我不想让我的双手因不必要的事情而更加忙碌。
