be busy doing sth 忙于做某事

正因?yàn)槭敲τ谧瞿呈?，所以可以想象為正在埋頭苦干的情景，用進(jìn)行時(shí)態(tài)是最合適的了。

【例句】

I'll call you later—I'm busy doing my homework. 我晚點(diǎn)打電話給你。我正在忙著做作業(yè)。

Mum was busy bathing the baby when the doorbell rang. 門鈴響的時(shí)候，媽媽正忙著給嬰兒洗澡。

【問(wèn)題】

Dad can't come to the phone because he is in the middle of talking to a client.

用今天學(xué)習(xí)的詞組，重寫上面的句子，保持句意不變。

答案：Dad can't come to the phone because he is busy talking to a client.