It's difficult to understand the principles of electrooptics.

Music therapy is very effective in reducing stress.

Abstract algebra is a field of mathematics that studies algebraic structures in an abstract way.

I am majoring in econometrics at university.

I am majoring in biophysics at university.

Biotechnology plays a very important role in the medical field.

He is an expert in sociolinguistics.

Chemotransmitters play an important role in the transmission of information between nerve cells.

He is an expert in fluid mechanics.

My father is an expert in otolaryngology.