Examples
wǒ我xiàn zài现在zhèng正máng yú忙于xiě写yì一běn本shū书。
我现在正忙于写一本书。
I'm now busy writing a book.
我最近真忙于我的毕业论文。
I've been really busy with my graduation dissertation recently.
我最近非常忙于我的毕业论文。
I've been really busy with my graduation dissertation recently.