I have been to Outer Mongolia.

I have been to Chicago.

The Paleogene period was a very important time in the history of the Earth.

He is the type of person who thinks it's a moonlit night if it's bright, so he only has a one-sided perspective.

He thought deeply and said, 'I think, therefore I am.'

He said, 'Where there is a will, there is a way,' and faced the difficult situation.

He strongly believes in the philosophical thought, 'I think, therefore I am.'

He always keeps in mind the phrase 'If one learns without thinking, it is a waste.'