Epidemiology is the science that studies the occurrence and spread of diseases.

I am majoring in political science at university.

I am majoring in physiology at university.

He likes going to chamber music concerts.

He is in the third year of junior high school, or in other words, he is in the 9th grade in school years.

He has a deep interest in numismatics.

My major is chemical engineering.

He used himself as a reflexive pronoun.

He is a world-renowned bacteriologist.

The history of the International Communist Party had a significant impact on world political history.