She was busy preparing lessons.

她忙于备课。

youdao

I'd tell her that I had no time to worry about such things, being too busy preparing lessons for the next day.

我告诉她说我没有时间去考虑这些问题，因为要准备第二天的课，我实在太忙了。

youdao

Each and every night, he's busy correcting students' homework, preparing lessons, reading and studying. Sometimes, he's still sitting there at work when I wake up at mid-night.

每天晚上，他忙于批改作业，备课，看书，学习。有时，当我在深夜醒来时，发现父亲仍在工作。

youdao

Mr Madsen said the teachers' time for preparing lessons would be reduced under the reforms.

BBC: Denmark teacher lock-out paralyses schools

The workload figure excludes time spent preparing lessons, attending meetings and marking pupils' work.

BBC: Call for Scottish teachers to have more holidays

The original McCrone deal agreed between councils and teaching unions, guaranteed teachers more than 12 hours a week to spend marking and preparing lessons in school.

BBC: Review of McCrone teaching deal announced