He broke new boundaries in the music world.

He has crossed that border.

This park is very rich in nature.

He naturally demonstrated leadership.

Solving problems of arithmetic sequence is difficult.

Understanding geometric sequences is important for understanding mathematics.

He is good at solving problems related to geometric sequences.

He is writing a thesis on phenomenology.

Phenomenology is a branch of philosophy that focuses on the study of human experience and consciousness.

The simulacra phenomenon of imagining a face from three dots is one of the characteristics of the human brain.