The Russo-Japanese War was a war fought between Japan and Russia.

The Pacific War, also known as the Greater East Asia War, was a war led by Japan, primarily involving battles in the Pacific region.

Hayaka is my best friend.

I learned how to calculate the hacoversine in trigonometry.

There are times when we perform calculations with the haversine in trigonometry.

Time flies like an arrow, a year passed in the blink of an eye.