Right now, I am in Tokyo.

He believes in psychic phenomena.

This movie was really fantastic.

He was recognized as a living national treasure of Japan.

Aito won a prize in an essay contest.

Nuclear fission is a powerful process that generates energy.

He is an expert in nuclear physics.

He said 'friend' as a noun ending for me.

Seeing his deed, I was surprised.

What does the axis of this diagram represent?