He doesn't easily open up to strangers.

This is my first Japanese class.

He was known as a quack doctor in that town.

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.

Asuna is my best friend.

You shouldn't laugh at his failure, because misfortunes can happen to anyone.

She announced that she is pregnant.