I am planning to go to Inner Mongolia, an autonomous region of China, next week.

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.

My father is fifty years old.

He is fifty years old and still full of energy.

Gojū is my best friend.

My father is fifty years old.

He came up with fifty ideas.

Mr. Goju is my neighbor.