He boarded the fighter plane as a tail gunner.

This ancient proverb, 'know the other side and yourself, and you will not be in danger in a hundred battles', teaches us the importance of understanding ourselves and others.

This is a model of a mutetrahedron.

The 正十六胞體 is one of the regular polytopes in four dimensions.

The 16-cell is one of the convex regular polytopes in four dimensions.

The 正六百胞體 is one of the regular polytopes in four dimensions.

The 600-cell is one of the regular polytopes in four dimensions.

This mutetrahedron has a very unusual shape.

Whenever he faced a difficult situation, he always said, 'The best of the Thirty-Six Stratagems is to run away.'

He is doing a special exercise to strengthen his flexor carpi ulnaris.