He is majoring in criminology at university.

He is an expert in pharmacology.

He is an expert in somatology, with a deep knowledge of the functions of the human body.

Gakuto is my best friend.

He is an expert in bibliography and works in many libraries.

He is known as an expert in gerontology.

He is an expert in malacology, focusing particularly on the study of snails.

He is majoring in analysis at university.

I love histology classes.

He is an expert in acoustics.