He does piriformis muscle stretches every day.

It is said that Yagamihime of Inaba was a very beautiful princess.

In learning Japanese grammar, understanding the upper two-step conjugation is important.

When learning Japanese grammar, it is important to understand verbs of the upper monograde conjugation.

He succeeded in a difficult project with the spirit of 'ishi no ue ni mo sannen', which means great works are performed by perseverance.

A tesseract is a four-dimensional geometric shape.

A 5-cell is a simple convex polytope in four dimensions.

This area is seriously contaminated with radioactive isotopes.

In organic chemistry, the concept of cis-trans isomers is important.

The study of filterable pathogens is an important part of virology.