Understanding the four-step conjugation in Japanese is difficult.

Koushirou is my best friend.

This box is perfectly square in shape.

This square box is very simple and beautiful.

I live in Yokkaichi.

My new car is a four-wheel drive.

He likes to speak using four-character idiomatic compounds.

He draws a four-panel comic strip every day.

The Quaternary is the most recent era in Earth's history.

He drew a tetradecagon shape.