We conducted a psychological test in today's class.

He engaged in psychological warfare in the chess match.

He is known as an expert in criminology.

He is an expert in computational linguistics and is involved in the development of artificial intelligence.

He has a deep interest in archaeology.

He understands the importance of learning.

He is majoring in psychology.

Gaku is my best friend.

Natural language understanding is an important field of artificial intelligence.

Polygyny is a social system where one man marries multiple women.