当妈妈把饭煮好，我正忙于功课。

When mum finished cooking, I was busy with my study.

youdao

约翰在忙于他的功课。

John is busy with his lesson.

youdao

那时，他正忙于准备功课。

At the moment he was busy preparing his lessons.

youdao

珍正忙于她的功课。

A. Jane was too busy doing her homework.

youdao

汤姆总是忙于他的功课。

Tom is always busy with his lessons.

youdao

此刻，我正忙于(各科功课的)学习。

At this moment I am very busy with my studies.

youdao

此刻，我正忙于(各科功课的)学习。

At this moment I am very busy with my studies.

youdao