His performance was perfect and without blemish.

In mathematics, a perfect number refers to a number where the sum of its divisors, excluding the number itself, equals the number.

This fish is completely farmed, and no capture is done in the natural environment.

He is immersed in the study of panmagic squares.

He is a perfectionist, and his approach to work is very strict.

He believes in the geocentric theory.

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

A terrestrial planet may have an environment similar to Earth.

He is an expert in geophysics.

He played a perfect fifth scale on the piano.