I have been to Tainan.

The history of Funan is very interesting.

My second son became a doctor.

Syonan is a part of Japanese history.

This math problem is really a difficult problem.

This math problem is too obscure, I can't understand it.

This math problem is very dense.

What is this, that box?

Learning about the culture of Southeast Asia is very interesting.

My house is located in the southeast of the city.