I studied as hard as I could to pass the exam.

He is working hard.

We started a collaboration for a new project.

We decided to collaborate on a new project.

He has contributed to the company for many years as an elderly worker.

He learned about the concept of synergism in theology class.

There are several words used as 働詞 in this ancient document.

He continued hard labor all day long.

He graduated from university for employment.

He started working immediately after graduating from university.