I am majoring in econometrics at university.

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

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

I am learning Simplified Chinese.

I have started learning Traditional Chinese.

This is a model of a muoctahedron.

Please remember this old proverb, 'The friendship of a gentleman is insipid as water.'

Japan's exclusive economic zone plays a crucial role in the management and utilization of marine resources.

He was playing by swinging the tree branch.

This is a 六角四片四角孔ねじれ正多面體, in other words, a muoctahedron.