It is important to learn about the prevention and treatment of the human immunodeficiency virus.

He found a leaf floating on the surface of the water.

I have an important job interview tomorrow.

My notebook has my daily schedule written in detail.

Please be careful as this slope is slippery.

She blushed in front of me.

He blushed with shame.

What is the area of this room?

On a hot summer day, cold sōmen is the best.

Please read this written document.