He studied history to understand the labor hardships experienced by ancient people.

It's difficult to understand his explanation.

In the park, people were playing happily.

Based on my experience, that method is effective.

I like to experience new cultures.

I like to study new languages.

It's difficult to understand his explanation.

She consoled her friend who was grieving.

He is working hard all day.

His daily travail is more than we can imagine.