Natural language understanding is an important field of artificial intelligence.

The depressed cowry lives quietly at the bottom of the sea.

The government declared a state of emergency to prevent the spread of the new coronavirus.

This country has fallen into anarchy.

Global warming is a big issue that affects all of us.

He is an expert in geophysics.

He believes in the geocentric theory.

A terrestrial planet may have an environment similar to Earth.

He is a perfectionist, so he is very strict about his work.

He played a perfect fifth scale on the piano.