他在大学里主修监狱学，专注于研究犯罪惩罚系统。

He majored in ___penology at university, focusing on the study of criminal punishment systems.

他在大学里研究刑罚学，专注于探索更有效的罪犯改造方法。

He studies ___penology at university, focusing on exploring more effective methods of criminal rehabilitation.