It is thirty-three kilometers to my house.

The Triassic period is one of the geological ages, referring to the period from about 252 million years ago to about 251 million years ago.

At what point in Earth's history does the Triassic period fall?

The Silurian period is one of the geological eras.

The Quaternary is the most recent era in Earth's history.

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

The Triassic period is one of the geological ages, referring to the period from about 252 million years ago to about 200 million years ago.

The Ordovician, an era name used in paleontology, is now called the Ordovician.

He turned thirty years old.

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