engaged in

1. 从事于; 忙于; 埋头致力于

She was engaged in protecting wild birds.

她致力于保护野生鸟类的工作。

She is now engaged in writing letters.

她现在正忙着写信。

engage in

1. 从事

He has engaged in farming for 20 years.

他从事耕作已有二十年。