She's preparing to write matric.

她正准备参加毕业考试。

《牛津词典》

However, I will not disturb you (seeing her preparing to write.) Youknow your own concerns best.

(见她准备写信)“你自己的事情你知道得最清楚。”

youdao

I dreamed that while preparing to write a composition in a primary school room I asked the teacher how to present a view.

我梦见自己正在小学校的讲堂上预备作文，向老师请教立论的方法。

youdao

In preparing to write this piece, I intended to subject the agenda of the Far Left to the same scrutiny of American public opinion.

FORBES: Tea Party Agenda No. 6: Repeal ObamaCare

As I write, Labour's Johann Lamont is preparing to lodge a point of order demanding a statement later from the FM.

BBC: College funding controversy