I believe him.

Please don't forget that.

The nodes of this tree are distinctive, aren't they?

Christmas is an important occasion when the family gathers.

He spoke to the teacher using respectful language.

He is a person who never forgets to show respect to others.

Kei is my best friend.

He always speaks in polite language.

This is a notebook for school use.

We need to make the most of natural resources in this project.