The twenty-four divisions of the solar year, or 'Nijyushi Sekki', is a system that divides the year into 24 parts according to the changes in nature.

My four treasures of the study are a fountain pen, a pencil, an eraser, and a ruler.

He is doing squats to train his quadriceps femoris muscle.

I saw a cackling goose in the park.

We have our wedding on the twenty-fourth.

A positive-semidefinite matrix is one of the important concepts in linear algebra.

Kunminjōon is a book for teaching the correct pronunciation of Hangul.

A tesseract is a four-dimensional geometric shape.

The tesseract represents a four-dimensional geometric shape.

The 正五胞體 is a simple convex polytope in four dimensions, having five vertices.