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 an expert in paleography, and he is good at deciphering ancient handwritten documents.

He likes to take a walk in the park at dusk.

We plan to hold the meeting in Western European Time.

We will start the meeting at 3 p.m. Central European Time.

I will start the meeting at 9 a.m. Eastern European Time.

This system enables real-time operation.

The time complexity of this algorithm is O(n).