He is an expert in probability theory.

Einstein's theory of relativity is one of the important theories in physics.

He is writing a thesis on the yellow peril.

His idea is pure armchair theory and cannot be applied to real-world problems.

Christology is a part of Christian theology that studies the nature and role of Jesus Christ.

He likes to take a walk in the park at dusk.

Mr. Hiruma is my best friend.

Well, let's get started!

The mesentery plays a role in supporting the intestines.

Interracial marriage promotes diversity and understanding.