He is an expert in topology.

I am very interested in sociolinguistics.

He is majoring in oenology.

He has a deep interest in parapsychology.

He is an expert in primatology and is engaged in the study of gorilla behavior.

She has a deep interest in astrology.

Cell biology is the study of the structure and function of cells, which are the basic units of life.

He is an expert in nuclear physics.

He is an expert in nuclear physics and has won many awards in the field.

He is known as an expert in psychoanalysis.