This math problem requires an understanding of functions.

He wrote a poem using the four treasures of the study.

You can use spectroscopy to examine the components of a substance.

Aren't you going to that restaurant?

This book has three volumes.

Don't you think his behavior is very strange?

His answer was unexpected.

He answered my question immediately.

A day has 24 hours.

It is difficult to find the optimal solution to this problem.