Einstein proposed the theory of relativity.

What year were you born in AD?

Protists are single-celled organisms that live in water.

He can always maintain his calmness.

We discovered a new planet.

Next year, my younger brother will have his coming-of-age ceremony.

He will become an adult next year.

Pluto is a dwarf planet located at the outermost part of the solar system.

While rotating on its axis, the Earth orbits around the sun as a satellite.

Pluto is classified as a dwarf planet.