String theory is a branch of physics that is a theory for understanding the basic structure of the universe.

He wrote a new paper on string theory.

He loves physics and studies it in the library almost every day.

I am majoring in physical chemistry at university.

He is a world-famous physicist.

He understands the importance of learning.

He is majoring in psychology.

Gaku is my best friend.

He has a deep interest in archaeology.

Among my family, I am the tallest.