他在大学里教授政治学，特别关注民主制度的研究。

He teaches ___political science at the university, focusing on the study of democratic systems.

她在大学里主修政治学，专注于研究国际关系。

She majors in ___political science at university, focusing on studying international relations.

她在大学主修政治学，研究政府与社会的关系。

She majors in ___political science, studying the relationship between government and society.