Oxygen, which is one of the chemical elements, is necessary for us to breathe.

I am an Earthling.

We are searching for extraterrestrial life.

The process of terraforming is part of transforming other planets into a habitable environment for humans.

Earth science is an important field of study for unraveling the mysteries of nature.

This painting is very valuable.

He is an infamous criminal in that area.

His calculating nature sometimes causes problems.

Looking at the bird flying high in the sky, I felt freedom.

He has a proud patriotism for his country.