He is known as a person with learning.

He learned Japanese through self-study.

He taught himself programming.

My toxicology textbook is very difficult to understand.

He has a deep interest in archaeology.

A construction worker is working at the construction site.

Mr. Kadokawa is my Japanese teacher.

He started his own independent business.

He proposed an original idea.

The hermit crab, known as 'yadokari' in Japanese, got its name from its habit of borrowing the shells of other creatures to live in.