He is an expert in ethology, and his research is highly regarded worldwide.

I used an optical microscope for an experiment at school.

Demography is an important tool for understanding various aspects of society.

He played a perfect fifth scale on the piano.

This fabric has high color fastness, so it is hard for the color to fade even when washed.

When it reaches absolute zero, the molecular motion of matter stops.

Your adorable smile brightens up my day.

This TV provides high-definition images.

I overslept today, so I was late.

The sphericity of this object is very high.