He is an expert in psychiatry.

He is an expert in physical anthropology.

He is an expert in physical anthropology, conducting research on human evolution.

Gestalt psychology is an important means to understand human cognitive processes.

Molecular biology is a field of study that understands life phenomena at the molecular level.

He is an expert in topology.

I am very interested in sociolinguistics.

He is an expert in algebraic geometry.

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

I am majoring in developmental biology at university.