The government is building a nationwide surveillance network.

He was deeply involved in the project.

He is deeply involved in the project.

The author's message is written on the opening page of this book.

I live in the Kanto region.

She sent an air letter to her mother.

He went to the archives to find important information.

She was going through puberty and was confused by the changes in her body.

It is important for each person to fulfill their role.

My high school has very strict rules.