I think his Japanese has improved quite a bit, hasn't it?

I am busy with work during the daytime.

He received the letter challenging him to a duel and began preparing for the duel.

Gender roles are an important element in defining individual behavior in society.

His role is to fulfill his responsibilities as a leader.

It is important to understand the importance of health.

He is working as an official of the city.

She is a very skilled seamstress.

He underwent a stomach plication surgery.

This is a historic building.