This train is running on the main line.

I live in Japan.

Ancient Japan was a place where beautiful nature and culture merged.

Do you understand the necessity of this project?

That information is unnecessary.

That information is completely unnecessary.

He thinks that war is a necessary evil.

Thank you very much, without your help, I wouldn't have been able to complete this project.

Thank you very much, your help was really useful.

I am deeply grateful for your help.